First things first "18 certificate"
But it is up the parents too sit down watch some videos of it (not trailers) and think is my childs mentality good with this?
My kid is ok with the likes of battlefield and co he is also ok with the likes of WoW or resident evil.
But silent hill is a big no and god of war is a big no (in the case of god of war it is not the visuals or story it is the game play it makes him angry it is just how he is mentaly and we avoid it)
Also is the child a decent loser? Is he going to get angry easily by glitchers/campers, will shit talking effect him emotionally?
Would he be ok hearing someone fucked his mom every 2 minutes? Is he able to grasp it is people talking shit or will he take it personaly.
No one on here knows that child better than the parents or if your a close friend you might know him well enough too assess if he is ok with it.
It is like movies, my kid sits with me and watches paranormal activity, terminators, night of the dead, alien etc etc and he is fine with it, we have fun.
But the likes of hostel and saw... not a fucking chance.
But mainly do you want this child playing mediocre games? Cod? Why not battlefield or battlefront.