The OnePlus 9 Pro supports reverse charging. To reverse charge a Huawei P20 Pro, you need to follow the steps below:
1. Make sure your OnePlus 9 Pro is connected to a power source and has enough charge.
2. Connect the OnePlus 9 Pro to the Huawei P20 Pro using an adapter and USB cable.
3. Swipe the drop-down menu on the OnePlus 9 Pro, find the \"Reverse Charging\" feature in the quick Settings option, and turn it on.
4. Ensure that the battery of the Huawei P20 Pro is low and that it supports charging via USB.
5. Once the reverse charging function is turned on, you can connect the Huawei P20 Pro to the USB port of the OnePlus 9 Pro.
6. When the connection is successful, the Huawei P20 Pro should start to accept charging from the OnePlus 9 Pro.
Note that reverse charging can drain the battery power of the OnePlus 9 Pro, so make sure you have a sufficient charge supply when you do reverse charging.
1. The Huawei P20 PRO cannot be reversely charged.
2. The OnePlus 9 Pro does not support reverse charging of the Huawei P20 PRO.
Reverse charging requires the device to have the corresponding hardware and software support, and the OnePlus 9 Pro is not designed for Huawei P20 PRO to perform reverse charging function.
3. Reverse charging is a relatively new technology, only some mobile phones support this function.
If you want to reverse charge the Huawei P20 PRO, you can consider using another phone that supports this function or use a specialized reverse charging device.
Use the adapter and data cable to connect the two mobile phones.