I agree with
@Ketchup, CCW is the standard.
The only difference between CCW & CW motors, CCW has right hand threads and CW has left hand threads. As the motor spins the nut is tightened. In quads this is a big deal. A quad motor will start and stop many times per second. In a plane, the motor is changing speed far less often. You can run the motor backwards without issues.
If you are building a twin motor plane, use both a CCW & CW motor to offset the torque.