I can see people really getting into just an absolute plethora of animals and the list thereby getting lengthy and out of hand. Especially if some collab options are individual animals and not outfits for them.
I think the best option would be for there to be an expandable/collapsable section at the bottom of the screen that shows you a LEGO game style character select. Then after collapsing the menu you can use W/S or the controller alternative to switch that animal's outfits around.
It'd be a pain if we had something like this but it was just a lengthy scroll simulator: