Custom skins

Would it be possible to create a hack that basically makes you have skins client-side. Like starting up a hack, selecting what skins you want (like awp asiimov FN, karambit doppler MW, etc) and then press "Inject" and it will inject them into the game like a normal hack would? Also would this work in matchmaking and on servers with sv_pure to 1? Even if it doesn't I'd still consider it pretty cool, since by modifying items_game.txt you can't get knife skins

I appreciate every answer/information, thanks in advance ^^