Really depends what you’re looking for.
I personally hate playing 3DS games on Deck, but I have had good experience playing several games using Lutris (Played God of War 2016, Elden Ring, and Marvel’s Spider-Man) on Deck.
Emulation on Deck has been solid, but I’ve mostly stuck to Switch, GameCube and GBA games. Pokémon Legends ZA ran acceptably as well. I have Tears of the Kingdom, but haven’t installed it yet.
Tried Kingdom Hearts 2, and it seemed okay, but didn’t do much outside of launching it.