Which is the fastest way to run Wii games? I would guess emulators also have faster loading times, but emulators are not banned.

As I see f.e. USB Loaders and such are not allowed because of this, but most of the time it is not pointed out in each game's rules. And who is checking anyway? There's no noticeable way of detecting if a run was done from disc or using a loader (unless someone is really dedicated in timing the loading screens).

So what's the state on this? What does the Wii speedrunning community know? I would also want to try running some Wii games, so I'm curious before I start.

Thank you.

This would probably vary widely from game to game. Might be better to ask the individual games you're interested in.

Most Wii games ban emulator and USB loafers because they artificially increase performance from the regular console. But @Lieutenant_Boo is correct, it’s up to the games’ communities to decide what they want to allow, so always check with the mods and/or the rules of the game.