I hope I can convey this idea accurately but i was wondering if zbrush can this? Can I sculpt onto a form that is locked? Like I won’t be able to alter the form that I am sculpting on, Like how makeup is sculpted onto a hard lifecast that way u dont alter the original form if you substract clay.
You could duplicate a subtool, say of a face. Keep one version of the face as the underlying form, and use the other to sculpt your makeup forms. That way you can visibly only work with additive layering. Anything that intrudes past the base form will be lost.
After you’re satisfied with the form you can combine the subtools and paint with color for blending across both surfaces simultaneously.