I'm vaguely reminded of the excellent Jackbox game Tee Fury, in which players submit slogans for T shirts and "art" separately. Players then get to choose from a few options for slogans and designs to make T shirts which are voted on by the group.

I have fond memories of laughing until I was in tears when playing with a group of friends over drinks during the lockdowns in 2020. Something about the process just naturally results in hilarity (especially if you're in a group where you can be offensive).

It's like exquisite corpse for t-shirts. Or, in your case, shorts.