Help finding a PVP FPS game for PC?

Overwatch! Overwatch every time. If you want something less cartoony maybe try Lawbreakers (although I don't think that's doing too well) Titanfall 2 or Battlefield 1. I wouldn't go for Battlefield 4, I can't get a server over 40 people on PS4

There are LOTS of PvP FPS games for the PC, its one of PCs major genres.

Try Plantside 2, which is a free squad-based PvP FPS shooter.

No one can mention PvP shooters without mentioning Overwatch, which is arena based but still a PvP shooter.

I've heard good things about the PvP in the Sniper Elite series.

A lot of people are playing Player Unknown's Battlegrounds (PUG).

There is also Counter Strike 2, again arena based, but exceptionally popular.

H1Z1 is a PUG competitor that some people like more.

Pc gamers don't really play fps multiplayer games they sell a 1/4th as many copies sometimes less if you like fps games your not going to have much of a choice you'll need to find a game that can cross platform I'd suggest paladins (it's free)