The Mate 20 Pro can charge only one device at a time.
The reverse wireless charging is automatically disabled when your phone's battery level is lower than 20%.
Wireless charging is slower than other charging methods so it is more suitable for emergency use.
If you want to fully charge other devices we recommend using standard chargers.
The device you want to charge must support the Qi wireless charging protocol.
The reverse wireless charging only works when both devices are turned on.