I am currently searching to have a secured C2/3 iink with an UAV in an academic project. We use QGroundControl as a ground station and PX4 on a pixhawk cube for our UAV. Did you find a solution to your problem ? I am thinking that Mavlink 2.0 is not secured enough to do this and I would like to add encryption to my messages in order to have secured data to transmit.
Thank in advance for your answer !