Tommy Vercetti, CJ, Niko Bellic, Luis lopez, Michael de Santa and Trevor Phillips.
Round 1: They are hunting each other in São Paulo Brazil.
Wei gets a silenced Beretta 92FS, MP7, Pump Shotgun and a Assault Rifle w/Grenade Launcher.
The GTA team gets a Desert Eagle, Micro SMG, Assault Shotgun, AK-47 and a RPG.
So he's gonna take down Tommy, CJ(who himself is basically a master fighter skilled in boxing, Cobra Style Kung-Fu, and Dirty Fighting) who can kill people in a few hits, Niko who is a highly trained shoulder and actually broke bones and beat people down in cutscenes, Luis who is pretty buff and is an underground fighting champion, Micheal, and Trevor in berserk mode who gets faster, stronger, and practically invulnerable to blunt force trauma?
CJ having all that shit is non-canon.
Wei Shen has mastered over 10 different style's and has fought against Masters, these people would be a joke to him, and yes, I've beaten all their games, Niko is slow, Trevor will not be able to hit Wei Shen even once, Trevor getting Berserk Mode does not make him an unstoppable force, he won't be able to move if he gets his bones broken.
Did you play the Island DLC of Sleeping Dogs?
Wei has fought more then 10 black belts at the same time.