After a few days, I think door works in two directions. I can emulate HoTT sensors now. It is also possible to listen other sensors on the half duplex usart when the HoTT receiver asks it. If it were a connected electric air module we can grap the energy data from it. So we don't need a schematic for measuring voltage and current of the LiPo and also a cell voltage monitor.
The name 'UAVOHoTTBridge' makes more sense then. I don't have any HoTT sensor now. The name would then ever right for the future.