New Idea for a Summoner Spell

So this is kind of weird and maybe it doesn't work, but you guys tell me whether it makes sense.

Imagine getting ganked as an ADC early by a Xin Zhao. You're farming under tower, but somehow he dives you and gets the kill. You get set back a few waves of cs and never fully recover.

I think it would be nice to have a summoner spell that you can only use with an enemy champion where using it on them pushes both you and them away from each other. This could allow for some pretty cool plays. Push that Xin into the tower after rolling away as Vayne and then condemn him into the wall. It could add some danger to ganks for dive junglers.

It might also be cool if using it against a passable wall will push you over and leave the enemy on the other side.