If it is XNA4.0, then porting should be without too much trouble. Create mg project (with netcore , copy your files to that project and then compile ). There is at least one method which isnt xna api anymore so need to remove some parameters. If you want to 1:1 xna, then you should test FNA. I have only a few #ifdef in my code which compiles with MG,FNA, and MG-web.
Forms, there is this project (I have not tested this so cannot say is this similar than Windows.Forms which I used years ago when I did a little game editor
). There is at least one method which isnt xna api anymore so need to remove some parameters. If you want to 1:1 xna, then you should test FNA. I have only a few #ifdef in my code which compiles with MG,FNA, and MG-web.