Global Offensive*
"set character models" what. You could choose your model in Source.
>Sci-Fi weapons
Tazers are real things. You can go out and buy one, and police use them to incapacitate criminals. Molotov roostertails exist, I don't know about the decoy grenades though. Also, condition zero had no weapons like that, you may be thinking of Counter-Strike Neo, the japanese arcade release.