Traya must be tanky and deal some damage. A cd and health set works will with a crit avoid arrow, offense triangle and protection cross and circle. Scio has to survive until he gets Held by Hatred so mod with speed and health. Defense or protection triangle and protection circle and cross. DN has to be fast to suck the bus dry so mod for speed and potency. Offense triangle and protection cross and circle. That is the basics. The specifics of the counter will depend upon the relics of the bugs. If there are no relics, the trio is a good understrength win. If alpha and spy are up to relc 3, you should add sith trooper and either another Sith like Opress or consider GAT if you can spare him. If there are more relics on the team than the 3 and 3, you will need to have relics on the trio. Scion is the priority, followed by traya and DN. The mechanics of the offense are straight forward, isolate or fracture brute, then kill alpha. If spy is ever available, kill him and spy can one shot your team one after the other. Once you have killed alpha, get poggle then soldier then SF until only spy is left. Spy is a danger until he is gone.
Assumes all zetas except DN leader.