Previous Thunderbolts rumors said the team would be Zemo, Thunderbolt Ross, Ghost, Abomination and Justin Hammer.
That could certainly work - though I wonder what that team would really have to do in this show. Falcon and Bucky certainly can't take down Abomination, unless the show gives them a convenient technological off-button like the Suicide Squad kill switches. Or the Thunderbolts could 'debut' in the show as the post-credits scene of where Zemo goes after this story is over, I guess.
In any case, I'd be really happy to see the Thunderbolts in the MCU. But I will be hugely disappointed if they don't include Songbird, at least, from the original team.