one more suggestion apart from the ones on facebook. As your plane is a twin-motor setup, if you use the 3.8.0 firmware set the two motors as separate outputs (setting them as ThrottleLeft and ThrottleRight) then you can turn more sharply using differential thrust for yaw.
Just set:
SERVO3_FUNCTION = 73 # meaning left throttle
SERVO5_FUNCTION = 74 # meaning right throttle
then set RUDD_DT_GAIN to the differential thrust gain. It defaults to 10, which means full rudder leads to a 10% differential thrust.