I'd be more concerned about what their name would be.
He was a Kaio, but not a Kaioshin. Gowasu attributed his incomplete diffusion to both Zamasu's being two of the same person, not because of having a godly soul.I really don't see why not. They're even closer than the Zamasus were since they at least have the same body. Zamasu's own status as a deity might have played a factor in his resistance too though. Wasn't he a Kaio?
Zamasu kept being Zamasu so I think it'd just be Trunks.
He'd be MSSJB MysticWhat color hair would he have