For this, you should probably go to the individual game leaderboards themselves. I don’t see a need for there to be a separate level leaderboard for All-Stars.

I think the original games should just allow 3DAS in their ILs, 3DAS is not the kind of game to have extensions or ILs or anything. All in all, just ask the community you're interested in if you can do ILs on Switch (preferably on their respective discord servers).

but they accept switch for category extensions, right?!?! if so, that's dumb