Global keyboard shortcut override conflicts for power users

Working on a Windows desktop tray application which listens to a global keyboard shortcut and provides a data readout from a device and sends the numbers (data) as key strokes to the application in focus, e.g. Excel. We are trying to decide the best candidate for the default global keyboard shortcut, weighing alternatives between function keys (F2, F6, etc) and more complex key combinations e.g., ALT+CTRL+D. The heart of the dilemma is that function keys are easier to use because the user does not have to look down on the keyboard and contort their hand(s), breaking the workflow. The counter-argument is that power users of (e.g.) File Explorer and Excel will find that practically all function keys are already in use and us overriding one of them will disable that shortcut in File Explorer or Excel or both.

Maybe this question is overkill because the user CAN override the default setting, but we are trying to make the adoption of the app as smooth as possible. Get the user up and running as fast as possible, hence the initial choice DOES matter.

My search attempts for statistics about how many users are true power users of certain apps, or how many users use how many keyboard shortcuts in specific apps on a regular basis did not yield anything useful.

To sum it up, what would be the best initial/default choice for a global keyboard shortcut (which will disable the same shortcut in another app) for a data readout and data forward app (from something like a barcode reader, e.g.)?