Activating touch-bar group for as long as you hold a modifier key

Hey! The situation is as follows: I have a BTT touch-bar:

And I want BTT to open some touch-bar group with shortcuts(

) only for as long as I hold down any of modifier keys(ctrl, option or cmd) as it works with fn key configured like this:

So are there any ways on how to achieve that? For now I tried to get closer to what I want by doing this:

But as you can see, it is not very convenient to wait several second until the group will be closed or press a key again and again )

Btw, it would be great is your solution didn't contain AppleScript, as it seems to be not the most energy efficient feature in BTT