Global Screen Rotation Option (In Menus or otherwise)?

Is there an option of screen rotation either in the RB menus or "the old school way" in a config file? Or since it's Windows and not Batocera PC for example, is it just a matter of setting the Windows Display properties to Portrait and then setting the Game aspect ratios to 16:9 (or 9:16, rather)?

Hello.
The best could be to wait for Retrobat V5.
There will be an option to rotate the game from the Retrobat menu. And with the collection "vertical", it will be easier to recognize them.