So I have heard and witnessed this matchup multiple times, but havn't really gotten a clear answer ever. Between Jinx and Vayne, setting aside skill and such, who counters who? I have seen games where people will ban vayne then pick jinx, which points to that one counters the other, but have also seen people, under this mathup, seeming to counter pick themselves.
So who counters who. And why.
Assuming equal or no supports, Jinx will win lane from her ranged harass. However, Jinx is very vulnerable. If Vayne gets a good engage support (voli, leona, blitz) she can easily win. If Vayne's support isn't good though (or Jinx gets a really good disengage support ie Janna), it's pretty likely that Jinx could get a few kills out of lane and snowball.
Basically, Jinx is the safer pick- but if you're confident you're better than your opponent or you have a good duo, you can crush with Vayne too.
jinx counter vayne for a couple reasons she outranges her out teamfights her and if there 1v1ing you can just put compers down and get free damange on vayne and jinx laneing is pretty strong, vayne is better in 1v1's and killing tanks i think at full build vayne does more single target damange but with jinxs rockets she can hit 3 people at a time if not all 5
