Swords are my wheelhouse, so time to post again!
Sora is okay, combining great whiff punishing on the ground with high damage output. There are even a few standout moves, like f-tilt and d-smash (full-body intangibility!). The problem is that he's really campy, and most top players don't like playing a character like that, so they naturally gravitate toward more versatile styles that let them switch between camping and aggressive reads. Sora doesn't have the speed/hitbox combination to play aggressively without hard callouts, and optimal Sora involves a little bit of platform camping, a little bit of air camping, a little bit of ledgestalling, a little bit of neutral-b pressure, and a little bit of sword zoning, besides all the dash-in whiff punishing. I think that's a hard playstyle to stick to if you're unfamiliar with it.
On Cloud, since
Thinkaman
brought him up... way back when Ultimate was released, I believed that Cloud would someday be the best character in the game, or at least top 10. There have been DLC, there have been nerfs and buffs (Cloud up-smash was a big one), there have been crazy meta developments but in general, despite years having passed, I am still just as bullish on Cloud as ever (top 20-30 range with potential to be better). Even in the very saturated swordsman archetype, Cloud is fantastic, surprisingly versatile with big reward and a gameplan against every archetype, with only big grapplers being hard. His speed + Limit camping shuts down most zoners, he can fight other sword characters pretty well (minus maybe Byleth who would likely murder Cloud twenty different ways), and he can zone out most brawlers. Heck, Cloud has an arguably better matchup spread than Roy when you look only at archetypes.
Cloud does have some really hard matchups (DK/Bowser/Meta Knight), but like, you want to shut down the stubby likes of Ness and Wario? Zone out with Cloud b-air/side-b.
You want to beat zoners like Young Link? Anti-zone with Limit and then wall out with your big sword.
You want to beat sword zoners like Lucina? d-tilt and side-b whiff punishing.
Need a Peach answer? Cloud is your man.
Tweek even thinks that Cloud does fine vs. Diddy.
Cloud's neutral is so versatile that he just has answers for everything. In fact, he's so strong in neutral that he has an arguably even matchup (according to sparg0) with
Pyra and Mythra.
Cloud's the real deal; you can't go wrong with a Cloud pick. Just... have a Byleth in your pocket for those DKs and Bowsers, if you're a sword main.