borrowed character
描いてみた 描かせていただきました 描かせて頂きました よその子 お借りしました よそのこ 人様の子
When an artist draws an original character which was originally created by a different artist. If an artist draws his own original character(s) with the borrowed character(s), or draws borrowed character(s) from more than one artist, also tag crossover.
Note that 描いてもいいのよ is not supposed to indicate a borrowed character. It is supposed to be used to indicate the original artist is fine with others drawing their character.