Explore vtourskin.xml. You see there default: skin_webvr_prev_scene hotspots. Learn on how to add other hs and adapting skin_webvr_menu_following to make them "float"
What you want to do with their on click is not relevant but I wonder how and what you want to load as next tour?
ah yes!
i didnt see those in the vtourskin.xml. But then i realized i used the older version of it.
After updating to the latest version of skin and webvr plugin, i added a custom VR button by duplicating an existing one in this vtourskin.xml.
Great tip!