Yes, if you take a 2nd primitive and append as a sub-tool to the original (first test the new primitive to be sure it gives you a sculpty map), you can use āProject All Toolā and a message will ask if you would like to also project polypaint which, of course you would answer yes.
Select the new mesh in the sub tool palette and have the one you want to project from visible and press project all. You may have to play a bit with the Projection Shell slider a bit as well as using the ZProject Brush to pick up any little details which donāt get picked up. It can be tricky to get these settings exactly how you need them, but itās worthwhile to learn how to use the projection feature since itās such a handy feature of Zbrush.
Itās also possible to just use the Zproject brush to capture and transfer the polypaint data from one mesh to another. Again, append the copy that will be receiving the polypaint as a sub tool and select it in the sub tool palette. Make sure the two objects are lined up in the same space as accurately as possible, select the sub tool you wish to transfer data to, turn off Zadd, turn on RGB and paint.