Can you put a matte finish over a gloss finish?
Also question is, can you paint matte over gloss?
If you paint over gloss paint with normal matt emulsion, it just won't stick and just slides everywhere. Even if you do manage to cover it, the shininess of the gloss eventually comes through again.
Also Know, can you put a clear coat over matte?
Absolutely not. In rare cases, maybe your aftermarket matte paint job has no clear coat, but if you get it from the factory it definitely will. In fact, it's actually the clear coat that makes factory matte paint look flat with its microscopic imperfections and “dimples” (read more).
If you want to update semi-gloss painted walls but don't want to sand and prime; or, if lead-based semi-gloss walls prevents you from sanding, it is possible to paint over semi-gloss walls with a satin-based paint without sanding or priming. Wipe the walls a second time with a rag and clean water.