The menu world settings do mention an option to select custom only world, but there appears to be zero documentation on how to create a menu world

• bind the Export Menu World key in the mc options
• boot into a world
• look in the direction you want the title screen to face
• press the assigned keybind (game might freeze for a bit, and report in chat if the export was successful)

you can do that in both VR or NONVR