I was about to say COD 4 and Advanced Warfare with paintball effects on, but then I realized a paintball game actualy exists. Greg Hastings: Paintball 2 is a FPS and pretty sure its child friendly, but I haven't actually played it so idk. What harm can you do in a paintball game?

Extreme Paintbrawl is a FPS with just paintball guns, but it's also considered to be one of the worst games of all time.

Slime Rancher

Portal?

I would say Overwatch is something that all ages can appreciate. It has that appearance of a Pixar film, the characters are pretty cartoony, and it's easily accessible to beginners. There's no blood, and I can't recall any cursing...worst thing I can think of is Reaper's Ultimate (and Reaper in general I guess).

You can try Banjo-Tooie, there are shooting minigames in which you hold Kazooie as your weapon and it shoots eggs. Not violence-inducing at all. There is also this section with Targitzan... lol that's as close as a kid-friendly FPS can get XD

I let my kid play FPS like Halo or Starwars battlefront. See no reason why not there not scary or particularly violent towards people.

And Wolfenstien 3D.

im not sure if its a fps but plants vs zombies garden warfare is a kid- friendly shooting game. i got it free on psn a few years ago and havent played it since

Counter-Strike: Global Lottery and Call of Duty: Loot Chest Warfare. These two are kid-friendly as well.

Nah, I kid. Chex Quest is the best kid-friendly fps ever xP