Whenever I try to play anything other than smash melee like mario party or mario kart I get desync on frame 18 or frame 0. And when I try to host a netplay lobby It doesnt give me a room Id only external and local. I tried multiple versions
You get a room id when you use traversal server. Update to the latest dev version, and maybe try strict settings sync. Otherwise you both might want to reset your config. (Either by deleting your config folder in Documents\Dolphin Emulator, or by creating a portable.txt file in the same location as your dolphin exe)