I think they can, over anodizing I don't think it will make a huge difference. If it were Parkerized steel, I would recommend having it bead blasted first. Cerakote adheres better to bare metal. If there is a layer of anything in between, that's just another layer of potential failure if it loses adhesion for some reason. Check with the applicator, they're trained up on the best practices and can give you a better answer.