It was certainly the other way around. You can paint polyester with acrylic paint, but you can't paint acrylic paint with polyester. Because the styrene will attack anything that is not 2k.
Everything without a second hardener component will cause problems during the mould making no matter if you use polyester or epoxy. Usually the plug won't release properly from the mould. In adition polyester attacks the paint, so that you will get defects all over the mould.

Would it be possible to use a barrier over the acrylic painted pattern such as ‘pva mould release’ or ‘advanced board and mould sealer’ do you think? Can I paint pattern coat primer over it or a 2k paint? Help I am desperate if I have to strip the lovely shiny paint from the pattern!

Should’ve asked before I know!

Notice in the same post when I said “poly and epoxy are compatible” I also said ONLY use epoxy for bonding.

In terms of having a plug made epoxy or poly, theyll play nice with each other when laying up a mould or pulling parts from it.

Jason

If you coat it, it would loose it's shine anyways. I had always had problems when using any 1k stuff, even when I used a 2k paint on top. Pva ruins your shiny surface, if you don't spray it very carefully. You could remove the acrylic with acetone and then coat the plug with whatever you want. That's just as much work as to coat the plug without removing the paint.