Would it work to replace the focusing screen with a uv filter sanded with high grit sandpaper?
Sure, but that wouldn’t be an adapter with NO focusing screen, that would be an adapter with a focusing screen made out of a UV filter. You can also make one with tracing paper or waxed paper as a focusing screen. Any of those options will result in varying levels of quality. An adapter with NO focusing screen would be one that simply focuses on an aerial image.