If you want to take 100% straight photos with the Huawei P20 Pro, you should definitely activate the level in the camera app. This will visually indicate in the viewfinder whether you are holding the camera straight for the photo.
However, the spirit level is not active at the factory, which is why you must activate it in the settings of the camera app. To do this, please proceed as follows:
1. Open the camera app
2. Switch to "Pro Mode"
3. Open the settings
4. Activate the following option: horizontal level
The level which uses the position sensor of the smartphone will now appear in the viewfinder image.
With the Huawei P20 Pro they should now succeed in taking a photo that was taken straight and not crooked.