A MyArmor Universal Smartphone Holder mounted on a Manfrotto Pixi Evo mini-tripod. The combination makes a great grip for your P20 Pro if you find holding the phone difficult for more than a brief period.
My own Pixi Evo has been replaced by a Mark 2 version:
Side profile of the P20-Pro mounted in the Manfrotto Pixi Evo.
The smartphone holder I use is this:
Three-quarter profile of the P20-Pro mounted in the Manfrotto Pixi Evo.Front view of the P20-Pro mounted in the Manfrotto Pixi Evo.In order to trigger the shutter while holding the phone aloft for a better view or even for shooting selfies, a small and inexpensive Bluetooth remote shutter release, like this, can prove invaluable.
Personally, I feel the official Huawei Smart Case for the P2o Pro is a must, but it can be removed easily when required.
You can buy the official Huawei P20 Pro Smart Case from Amazon: