have set up tailsitter to this vid,servos work in FBWA but not in QSTABILIZE, intended or not?
The Servo on the Tailsitter plane operates after Arming. (QStablize)
Remove the propeller and hang Arming to raise the throttle slightly and test it.
If indoors, you may need ARMING_CHECK = 0.
After testing, change back to ARMING_CHECK = 1.