TL;DR: Move it to either "Community" or "Players' E&C" category.
+More appropriate: Really, how do arts about the game NOT related to the game? "Off-topic" is a wrong category for it, so the change should fix this problem easily.
+More exposure: "Off-topic" isn't as frequently visited as the other two, yet players' arts (The word "Arts" in the context means more than just drawings/illustration) should always be valued and commemorated. The change will shed more lights to this category, as well as motivating those who wish to devote more time to making them
That's all the reasons I have. Feel free to share your opinion here!
Thanks for reading!