Now I don’t mean the Zamasu who is in the main storyline that was awesomely destroyed by Berus, I mean from Trunks’s timeline.
Prepare yourselves as the name Goku and Zamasu is going to be used a lot and I will try and make it as little confusing as possible.
Now we also know that Black Goku is actually Zamasu. The other Zamasu working with Black is either from Trunks’s timeline, or from another timeline or visa versa.
This is yet to be explained with fans getting more and more information on everything by the week.