Team Deathstroke. Paired as you have them, Deathstroke and Batgirl win, Batman stalemates Daredevil, Green Arrow stalemates Hawkeye, and Connor and Nightwing die terribly. Bats/DD and Hawkye/GA keep fighting. Deathstroke murders Panther, Batgirl beats up on Punisher. Those two help Batman and Green Arrow, and game's over.
Team DS is also the better team when it comes to prep. (barring calling in reserves... cuz then Panther would bring Wakanda into this) Deathstroke is easily the most powerful person here, and is quite capable of taking on several of the opposition, if need be.
Team 'Stroke, 8/10.