Trackpad App Switcher's Gesture Mode for custom key combination?

Hello all,
Just switched to Mac and immediately purchased license of BTT and have been enjoying the smoothest gesture controls since.

I see there is a "Gesture Mode" seems to be specific to App Switcher which emulate holding down cmd & tab to switch to different apps, wondering if this "Gesture Mode" could also be used with custom key bindings? (Holding down 1 key while pressing another key repeatedly using tip-tap gesture, until all fingers lifted to release the held down key)

This could be useful in cases such as using BTT to emulate alt-tab in vm/ remote desktop or even implement cmd-shift-tab to select previous app in app switcher.