Unfortunately this is totally unviable, one of the things your client loads up when you are on the map loading screen is all the skin models from all players (Since the server needs to load up every single gun model so they can properly display it on the ground and on the player hands) so if Riot decides to insert this feature the game will be WAY heavier and probably full of performance issues, imagine for those (like me) who collect every single skin?

But ngl I would love to have that :P