New Idea For A Game Mode

I had an idea that probably a lot have had already, but i'll share it anyway. I think it would be fun if riot release a game mode, where you can play a certain champ with the champions passive, but you get to choose abilities from different champions. Take one Q, one W, one E and one Ulti or choose 3 basic abilities and one ult, so you could have 3 "Q's" or something. This would be on sums rift and the game would carry out as a normal game. Maybe tweak gold or xp but nothing big. If any riot employee reads this i'd like to get insight also whether this is even possible or not with current technology.