Here, you can find out what areas of the internet are allowed to be a part of these tournaments. Keep in mind that the reason why there are restrictions are because people have multiple identities that could take more than one slot. This is a form a cheating.
VTubers (Extends to PNGTubers, but not Pre-Debuts)
Friends and other assossiates
Smack Studio Community (Only people who I know in some extent and approved)