I mean, the Vees from Hazbin Hotel had barely any screentime and they still were in the Villains Wiki.
I have one character from my animated webseries that has a fully fleshed out episode and character arc. Could he be on here?
Well, as a little friendly advice, if it's something completely original of your own invention, then I don't see why not. After all, everything good thing starts with an idea.
In support of everything stated by @Dylan Pietz remember the spoilers protocol if they happen to be upcoming villains.
What do you think?