There are exactly three characters I who never ever enjoy fighting. The rest vary.

Aegis, Sora, and Duck Hunt are always annoying. I have never enjoyed a single match against any of these characters.

Aegis: Huge, oppressive moves that are completely safe. It's impossible to punish a ton of her moves unless she attacks facing the wrong way on accident while right next to you.

Sora: the lock-on dash move is obnoxious. Every single Sora I play against spams like three moves, and it's much harder to counter than it should be.

Duck Hunt's entire design is hiding in the corner and piloting a dumb projectile. It's one of those super obnoxious quirks that you have to memorize or get punished by, but it's also the entire playstyle. There are like 90 fucking characters. If I have to learn how each of your weird one-of-a-kind projectiles works in order to not play "get juggled simulator" then your character is dumb and so are you. Talking to you Hero and your Thwack bullshit.