Tailsitter with differential thrust problem

#1

Hi everyone
I’m trying to use Pixhawk 4 with PX4 firmware as Caipiroshka Tailsitter airframe.
Lately I was trying to take-off in fixed-wing on a trolley.
But I couldn’t control yaw since there’s no differential thrust operated.
Is there anything I can do to turn on the differential thrust on fixed-wing mode?