How to add properties to menu items that are editable via experience editor

I am building out a mega-menu that contains category-specific images/watermarks that are placed within each respective menu item’s dropdown. I see you can add global properties to a menu, and that you can add properties to menu items via the API, but is there a way to add item properties that are editable in the experience editor? Or possibly a way to relate content held in a document type to a specific menu node?

Unfortunately menu item properties are not editable in the experience manager. Relating menu items to documents is also not exactly possible. Though obviously you can relate a document to a menu item, this is meant to link that as a target url. You’d have to do the work in the frontend to stitch it all together.