There are a lit projects that doesn't disturb nintendo's lawyers. Nintendo doesn't like it it people make money with their brands, take money away from them or hurt nintendo's reputation. The Pokemon fan project ura####, got shut down because they try to get money with it, but pokemon ######(not sure if against rules) online is a online none profit project that is online now for years. You just have to understand nintendo. Alternativ online server for nintendo games, seems to be fine with them.
I wanna say yes but I haven't even scratched the surface of emulating yet so I'm not sure: Still have an absolutely massive backlog of Steam games to play through. That said, I heard Emudeck is fucking fantastic!
Because he wasn't talking about nintendo games, he was talking about the fact that the steam deck doesn't have some proprietary cloud for all the games.