Yargis - Space Melee, a Windows XNA game, uses GraphicsAdapter.get_MonitorHandle(). In Proton, with Wine Mono's FNA-based replacement for XNA, it crashes with a NotImplementedException. On a single-monitor system, I confirmed that hacking it to return an HMONITOR for the primary monitor gets the game further.

Adding this capability to Wine Mono requires mapping from an SDL_DisplayID to HMONITOR. One could attempt to do this using the display name, but that seems complicated. Maybe SDL_GetDisplayBounds combined with MonitorFromPoint would work, but I'm not sure if I can assume that monitors do not overlap.

A property, similar to SDL_PROP_DISPLAY_WAYLAND_WL_OUTPUT_POINTER, but available on Windows and mapping to HMONITOR, seems like it would be cleaner.