Hi! Do you still need a solution for this?
If yes, I’ve found that you can hide ALL scrollbars (including in hover previews) using a plugin called Hider.
It also allows to hide other stuff but you can choose what to hide (although, if you toggle “hide scrollbars” it will hide ALL of them throughout the whole app - I personally like it this way but it may be a con for some people).
Hope this helps!