After watching the BAYMAX! on Disney+ which I have liked a lot, I have this idea in my head.
If Hiro had created a multiverse portal for Baymax to help anyone other than his world.World I have in mind:
RWBY
My Hero Academia
One Punch Man
Dragon Ball Super
High School DxD
Demon Slayer
Hunter x Hunter
Jujutsu Kaisen
And that's it, if you want to add other worlds in the story or delete some I don't mind.
(but for me the world of RWBY and My Hero Academia are perfect for Baymax to travel).