Sort Champions by Skins

Simple. I think it'd be cool to be able to sort your champions by those which you have skins for and those that you don't. Or at least add some sort of filter to view only champions you have skins for. I've been doing a lot of mystery gifting and so I want to see the champions that I have skins for/how many I have skins for. I can just manually go through it, but that's kind of a pain tbh.