I mean, I can. They’re in the game.
A Dark Samus with her own moveset, wouldn’t be.
Despite not having an entirely unique moveset, they are playable. It may not be the perfect representation of the character, but neither was an Assist Trophy.
The perceived value of clone characters compared to unique newcomers is entirely determined by the fans who play the game. I’m really not sure how else to say it. We could deal with hypotheticals of certain characters being different but the reality is that they weren’t planned that way.
It was either Dark Samus and Chrom as Echoes, or not in the game as playable at all.
Only reason clones have any significant Value is because of newcomers. No one would be that hype if Sakurai stated that every newcomer would be a clone of someone. This is where the core of echos come into play, and why they're not as valued as original fighters, and probably why Sakurai doesn't consider them "newcomers" and made that statement at e3 about expectations. They have value BECAUSE they are also mixed in with unique fighters. Sakurai said there's only a few more fighters left which implies for newcomers means around 3-5 IMO which makes competition for Isaac, SORA, Llyod, Pokémon, Geno, Banjo, Skull Lid, Surprise characters, Xenoblade, etc.. much more fierce.
Imagine if Banjo/Geno/ Sora/ Skull Kid etc. was just a clone. A lot of people would be upset.
Would fans be happy even if they were clones? Probably after Stockholm Syndrome kicks in. The perceived value for them and to outsiders (especially) would drop considerably vs if they were original and fresh. Not everyone likes having their wanted newcomers being an echo because there are instances where the character they're based off of is not enjoyable to play for them. I absolutely dislike the way Fox plays and will never play him but I extremely like Wolf. Imagine for me if Wolf was a echo of Fox; I wouldn't be that happy due to my favorite newcomer having a moveset/style that I cannot enjoy. You can make wanted speculation about the likelihood of a character getting in because of echolocation, however we saw Chrom being a 90% Roy clone when people thought he was going to be an Ike one. Dark Samus fans have valid criticisms for their character being Samus 2.0 when they had assets and animations in Smash 4 of her assis trophy. This is not to say that certain characters cannot be echos but to point out the bias of people being okay with echos. What if SORA/Banjo/Isaac/Elma/Geno/Lloyd were clones of other characters? Most would outright say it wouldn't make sense and be stupid. Why is it that people are okay with Dark Samus being Samus 2.0. Dark Samus also doesn't make sense since it plays nothing like Samus in her games. The only sense it makes is from an developer point of view of it having a similar proportions to Samus and thus being easy to implement regardless if it doesn't fit the character or her source material. Ganondorf in the past being an Falcon clone also didn't make sense considering all his source material he has but was added because of ease from a developer PoV. Would people still want Isaac if Sakurai stated he would be an echo character? Would people say that he wouldn't be Isaac anymore if he didn't have any source material in his moveset? Say hello to Ganondorf (maybe people are okay with him having a sword now????) say hello to Dark Samus who also fit that same valid complaint from their fans (at least l it's floaty looking). Is it worth the inclusion if it means they feel out of character with their source material? That is how Sakurai felt with Ridley; he didn't want to add a heavily requested fighter and not make him feel like Ridley which is the main reason why Sakurai said he would be extremely hard to implement (which he again pointed that out during the TreeHouse of having a very hard time.)
Any character could be an echo if they have similar proportions to a character already in Smash (hello to a lot of human/humanoid characters) from a practical point of view. People's bias on the character largely determines just how acceptable it is for a character to be a clone. You didn't hear not one K. Rool fan speculating or being okay with him potentially being an echo. Not everyone actually likes the style of the original character echo fighter is based off. Yeah you can tell me I should happy that my requested character is in, but what if my character happens to be based off of the character that I do not enjoy at all (Fox???). This is not me criticizing Sakurais choice because I understand how long it takes to make brand new stuff in the age of HD graphics and all the testing etc. This is me finding just how interesting it is for people to speculate on echos, the very concept of clone characters in vacuum (what if newcomers were all just clones? The perception does not look good), and just who could be an echo based off the said person respective bias.
I don't really have an opinion on clones as a whole, as I only seriously use characters that are good regardless if I have a connection with them. My only critique would be to keep clones exactly a 1:1 replica; that way you don't have instances where one is better than the other (Dark Samus being the biggest offender here). As always, campaign for your character to be apart of the DLC train so that they are top tier if you care about viability that is. It worked for Cloud, Bayonetta, Corrin, Ryu, and eventually Mewtwo :D
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I also find echolocation a fitting term