Keyboard Maestro will allow you to do this.
It will intercept key combinations directly from the keyboard e.g page down.
I find the best way of using these is to get keyboard Maestro to send MIDI to QLab .
e.g using page down to send MIDI note 60 to QLab
Tis will even work with other keys being pressed to control the frontmost app
e.g Zoom is frontmost
Space is held down to temporarily unmute microphone in zoom
While space is down page down is pressed and QLab go is triggered
Mic