Error Message after Changing Model's Parent

[ComplexMetatable]

You can set the Archivable property of the character to true prior to the cloning, according to this post:

How would I create a clone of a player in-game?

I was wondering how I could create a copy (or multiple) copy(ies) of a player in-game. I at first thought that I could change the humanoid’s CharacterAppearanceId, but then I realized that that only exists in players. The thing is, I can’t add a player either (because of privacy issues) How would I make clones like Clone Tycoon 2 did for their arena?