Cold Hard Capital, Ammunition for Anna.
Most Fire Emblem players recognize Anna quite easily, and her innate hotness, whimsicality, general likeability, love of capital, and fighting ability – all most aptly falling in with Smash's style – is certain to attract those who do not know her or the series at all, she would attract people to Smash Brothers as well as Fire Emblem. Anna, in addition, is incredibly unique, there is no other character in any other game that can be adequately compared to her as per the nature of a Fire Emblem character among other things, making many a combative analogy fall flat on their faces. She is, beyond a doubt, the most reasonable and believable character which can represent many novel features of the Fire Emblem series which her contenders cannot.
Anna, as a character in Super Smash Brothers, is not bound to one representation like most characters, but rather she is a vast array and fountain of all her sister's acquired knowledge, the greatest progenitor of their accumulated knowledge: “[Their] family keeps a detailed log of everything they've each experienced, made from letters that they've each written about their journey. From a young age, each Anna is required to read the log in order to acquire all the information and knowledge contained.” Therefore, when weighing her against any other potential representatives, if one must weigh them, the sum – not the average – of all Anna's roles is the standard they should be held against. Most certainly they would be hard pressed to match her impressive résumé; She is the face of DLC with many episodes expanding on and showcasing her, she is a recruitable player character of the trickster class, she is the special merchant in every Fire Emblem game outside of Gaiden which did not use shops, she is the host of tutorials, pause screens, general menus, data systems, and all other internet or link interactions such as within the GBA games. There is, then, something to be said for future remuneration, this résumé can only grow in significance as time passes.
Anna's recurrence as a Fire Emblemier is far more than the simple concept makes it out to be. First, the argument that she can be easily replaced is null against Anna, in fact, it boosts her significance, the mere fact she could have been easily replaced in all of her respects, yet Intelligent Systems chose to keep her, as firm tradition, for those variety of roles, they even expanded her beyond those traditional roles, Intelligent Systems is not looking to replace Anna any time soon, she is, in fact, the least likely character throughout the series to be replaced, while as the series continues, lords will be replaced more frequently. Second, considering the nature of Fire Emblem characters, one name has, in its default presence, a much more weighty and lofty power than characters from other series, both in lesser quantity and higher quality, in personality and utility, in story impact and character interaction, they cannot be compared to Pokemon or any other series fully or easily.
One cannot think of inclusion solely based upon story impact, such is a major case for any given lord character, nor can one base inclusion of a character upon utility through 'non-essential' roles alone, such is the case for Toad, Mii, Wii Fit Trainer, Villager, Duck Hunt Dog, Master Hand for crying out loud, Multi Man Melee Wire Frames, and so on and so forth, they have no or little story to speak of, nor should one put story significance over another in any one particular series, they may have clear utility choices who have minor story impact which are very viable and could bring a great number of uniqueness to Smash. Whereupon people speak of a healthy balance of these two, along with the many other things they should consider, Anna's favorability in their rosters should skyrocket, indeed, for her choice is a healthy one.
Anna's impact on Fire Emblem can be likened to the Gold Coin in economics, a seemingly far fetched, and strangely appropriate analogy. Money is a medium of exchange, the most marketable good, nothing more, nothing less. The Gold Coin is one such of the many possible examples, it is easily replaceable with other forms of currency, its ever present competitor and often used secondary of a two currency system; Silver Coin, its historical combatant and the original, earliest, and worldwide used example; Cattle, and its current and most powerful replacement, that which allows the greatest movement and flowing of capital and production the world over; Paper Money. Yes, replaceable, yet countless video games, fantasies, worlds upon worlds, use this specific currency, not because it had a deep story impact, as the Gold Coin had in hyperbolic amounts, but because it is a tradition, the quintessential example of the exchange good, though easily replaced and negligible, that is so chosen by the market at hand. The story impact of the Gold Coin bears similarities with Anna's inclusion in the story, being the face of DLC with many stories focused toward her, as well as being a minor Player Character (similar to Tharja, Kellam, Lon'Qu etc.), the specific Gold Coin surely played an important flavoring role, but a dispensable and easily supplanted one nonetheless. In economics where it is concerned, wealth and capital is not a goal, but it is rather wished to satisfy more gratifying and subjective ends.
Intelligent Systems, under these ends, use Anna for their ends, they create this lovable and personal character that everyone recognizes as a humane (though some would not say so due to her dislike of socialists and labor theory) face of utility. The utility impact Anna has had is small, she is the character of non-essential that becomes only the face of utility, nothing more. However, when utility is excogitated accounting for her story impact and illustration as a powerful tradition as means to Intelligent System's ends, she is no longer the face of utility, rather, all the weight of her utility - as the ubiquitous caricature of mercantile pursuits, as the constant tutorial giver, the menu guide, and at last as the one who connects and guides players to the Outrealm, to other Gameboys, to the internet and all other networks, her novelty, iconic stature, and metastory (fanon and the like) - is thrown behind her weight, every single utilitarian, and other, thing she embodies becomes a sudden necessary as a component of her character and story. It is extremely unlikely she will ever be replaced by Intelligent Systems, she becomes, in fact, the least dispensable and most important and powerful singular character in Fire Emblem, carrying more weight than a singular lord, but perhaps not any lord.
Anna's position is so unique, there are barely any practical limitations to her moveset. As a combat merchant class unit, Anna wields polearms, lances and spears and the like. As a trickster player character, her magic stat is higher than her strength stat, and she holds blades backhanded, lending most handsomely to her use of a special sword she is often depicted wielding, the Levin Sword. The Levin Sword is an angular and zig-zag bladed, much like a Flambard or Javanese Kris dagger, I guarantee as a practitioner and student of weapon play (the Noble Science or European Martial Arts, Kenjutsu, Kali and other dagger play) that there is much to be had in these things for sword striking alone. Yet there is far more to her possible play, the Levin Sword is used in the game exclusively to deliver magic attacks, in the same exact manner that any magic tome user in the Fire Emblem series would deliver a Thunder, their utility then, must be considered equal, for the Levin Sword can easily be slightly tweaked to deliver all other forms of magic attacks. Perhaps even more interesting is her use of staffs, staffs in the Fire Emblem series carry a variety of roles, such as teleporting others and teammates, healing, healing oneself, mending weapons, and resistance buffing, but since neither her Levin Sword nor Staffs are melee weapons, either could be taken under artistic liberty, as Sakurai-san has done with the Fire Emblem characters numerous times before. Staff play and polearm play is often interchangeable, these things so far lend her much leeway for much of anything, even the heals can be implemented well, all items and weapons in Fire Emblem have durability, after a certain amount of uses it will break, the fact that Anna has no special unique weaponry allows the ability for durability mechanics. In addition to her default Trickster abilities, she has default skills from the the Theif class, and another viable reclass to the Assassin class, which uses bows and also handles swords backwards. Heck, if it would be possible, her ability could be extended to ridiculous extents, to which she can also reclass to the mage class line, leading to sorcerer, combine that with their hexes, and elements from Olivia's dancer class, and the numerous rally abilities and staff play, she can become a pseudo charge character and status effect character, like some weird combination of Blanka or Guile or Dictator and a Persona or Shin Megami Tensei character, all wrapped neatly in Fire Emblem. Undoubtedly there is far more here yet unexplored.
It is plainly clear, Anna is a good choice for the position as Fire Emblem representative, she has many extensive, unique, and powerful traits that all point toward her viability. There is still more to Anna than is here, much of her character, personality, and potentiality is still unsaid, and I encourage you to check out the series of Fire Emblem, surely there there is even more support waiting for you there, sleeping.