The start of all custom ROM development on Android usually begins with a custom recovery like TWRP. Without a custom recovery, it’s usually impossible to flash a ROM. Stock recovery checks to see if the software you’re installing is official, by way of signature verification. A custom recovery usually disables this, allowing you to just install whatever zip file you throw at it. Oftentimes there are issues at first, and on the Honor View 10 and Huawei P20/P20 Pro custom recoveries like TWRP couldn’t decrypt the data partition on the device. This meant if you wanted to make any modifications to /data you had to format your entire phone to remove the encryption and flash a modified Magisk. Thanks to XDA Senior Member Pretoriano80, users of both devices will be able to keep their phones encrypted if they want to modify /data with a custom recovery. You can check out the download links below for your device!
TWRP for the Honor View 10
TWRP for the Huawei P20/P20 Pro