For milsim games the camo color for each team is set by the host. Mostly green vs tan from what ive played. Black is not really used in the games i have played in. Unless its camo pants and a black shirt. Smaller games dont have set camo rules and you can run what ever you like.
As for camo choice. Multicam and Atacs seem to be in demand at the moment. You cant go wrong with good old cadpat for outdoor.
At the end of the day it comes down to what you like and what works best where you play.
Play with Honor. Call your hits.
Nothing just happens, You always have to strive...