Hotspot with animation

[Popov72]

Maybe this thread can help:

How to create Sketchfab like annotations with Three.js?

not sure what does the texture change here, but https://jsfiddle.net/x5321dby/ all it does is simply draws the slightly transparent copy of a cube (marker) on top of everything. when not occluded, it draws on top of itself but since it is identical, the result does not change.