I got sidetracked so I'm a little late with this reply.
The Ness and Lucas example is a fundamentally poor one, because they weren't trying with that for the echoes. You could argue how much of them is even the same base. I just...how can you even deny their different designs when almost everything about them is different?
Look, I only brought them up as a comparison and not to get into a discussion on the intricacies of copying frameworks. This goes way off topic and honestly I'm just not interested in discussing it. If you can't understand what separates the Star Fox crew from the Mario crew despite them being close-range fighters then just leave it at that. Lots of franchises have similar bases that are tweaked and changed to make them different fighters. I only brought them up to show how you can make things less lazy and not to get into a discussion that you seem to be fundamentally misunderstanding.
Conversely, echoes, and this is not just limited to FE, are generally very lowe effort. That's the point. They aren't even given their own numbers. You can argue Roy, but he's more in the camp of Falco compared to Fox these days. This is not just a FE thing. Daisy was literally patched to be more like Peach, Dark Samus is almost exactly like Samus, same with Richter and Simon. That's just how they work. If you have problems with echoes, that is not really a sword, nor a FE issue, that's an issue with how echoes are done.
Correct, that is the point. That has
literally been my point in this entire tangent. We are literally saying the same thing which is why I'm confused we are still even on this tangent. The FE echos are lazy and very samey like a lot of echos. And you are correct that this isn't exclusive to FE echos.
The problem is that these echos are concentrated in one particular archetype. It's one thing if these were spread out among the cast, but swords are where they are concentrated. This doesn't help with the "samey" feel. Then you add on how Ultimate further streamlined and reduced a lot of these characters to fewer moves and variations and it is then not hard to understand why people have a problem with this type specifically.
You look at Marth in Smash 4, and while he was still a Fair monster, there was more variation in things like Jab combos (looked smooth), Perfect Pivots and similar tech adding more movement options leading into awesome tipper reads, the tech window being much less lenient leading into surprise stage spike kills (perfectly timed run off Bair anyone?), actual kill throws making him more of a threat at high percents, and the usual combos associated with him.
You look at Marth vs Lucina in Smash 4 and there was actually a difference between the two. Lots of people would always say that Lucina was a worse version of Marth, but that was exaggerated. There were enough situations where you would think "Lucina would have killed there" that made her legitimately her own character and she fared at some MUs better than others.
Marth in Ultimate is significantly worse and less fun to play. The constantly shifting hurtboxs, insane levels of safety, and large amounts of burst options make tipper consistency difficult. Not only has his throws been nerfed leading to difficult high percent battles, but he lost his easy Jab confirms. It really leads to him being camped easily and being slowly chipped away at until the opponent can land a much easier kill move. I'm not interested in getting into tier discussions, I'm more speaking on how not fun and rather stressful it is to play him in this game.
And contrary to 4, Lucina actually is a better Marth. Yes, Marth still has cool combos and kill confirms, but that's after getting through the awful neutral. Lucina is much better suited to a game where the concept of spacing has largely been destroyed thanks to being able to safely jump half of the stage in one shorthop for most characters. When your character is largely relegated to Fair, Nair, and D-Tilt then the more consistent one is generally the better one. Especially so in a game where consistency seems difficult to achieve regardless of character.
We can talk about my needing to be better with Marth or be a better player in general, but it is true that he's largely been dropped from even notable Marth mains. Even the current best Ultimate player and most notable Marth main (aside from M2K) MKLeo dropped him for Lucina and subsequently dropped her for Joker. I've noticed that lots of sword mains dropped their characters in Ultimate, even the die hard Ike mains that refused to do so in 4. Even Lucina has been falling off in popularity among competitive players (well as far as I know), so I don't think I'm alone in my feelings.
I think Ultimate's engine and mechanics makes the type of spacing most of the sword characters were designed for less fun and more difficult than previous Smash games. Roy and Chrom are seeing lots of popularity still, but they also are designed to be the polar opposite of what most of the others are. People complain about the disjoints swords have, but honestly sword characters are harder to play than they are to beat. The swords are either too stubby to matter in a game with as much burst and acceleration as this one or lack any sort of multi-hit that can't be easily spotdodged and then punished. Chrom and Roy are annoying because of their speed and safety and not because of the disjoint.
I also feel that Corrin is the same way. You might say the pin was busted as **** in 4, but I don't think it overshadowed the rest of their moves that much. But it was a legitimately interesting move that made Corrin feel fairly unique and helped set things up for lance tippers and other things. The one in Ultimate might be more balanced, but it is also more boring as a result. I had lots of fun sniping with tippers in 4, but it feels significantly harder to do so in Ultimate. In an effort to balance Corrin towards using the full kit it just feels like I'm once again mashing with swords most of the time.
And we might say that again I just need to get good, but it feels like the type of spacing I was used to is gone when jumps are the safest movement/evasion/offensive/defensive/panic option in the game. With the aerial acceleration and safety being what it is I feel like I'm just mashing sword aerials the entire time once again and the only time any other move comes out is in advantage. I can only take so much aerial mashing before I'm sick of anything resembling it.
So, it is correct that I don't think this is a sword characters fault and the problem lies with Ultimate's design. But as I already stated I think sword characters are the worst about it. Even setting aside clones/echos/whatever there's only so many times I can mash a sword Fair/Nair/Up-air before I get tired of it. They are the least inspired of all the movesets in the first place and so I feel a lot of it comes down to their general flow and movement. Ultimate significantly limits that by allowing really dumb things like being able to roll/airdodge across half the stage,
through active hitboxs, and end up behind the opponent and then immediately Fsmash or otherwise act out of it. That naturally incentivizes the kind of aerial mashing we see to avoid being caught with things like that which then ruins what was interesting about this archetype.
And that's ultimately why I strayed to more close-range and aggressive types because they seem to have at least a little more variety in their mashing.