I just finished and uploaded my LineageOS-20.0 build for Huawei MediaPad M5 : Schubert ( SHT ) There is a Thread on XDA from Surdu Petru, who started the project some time ago. Unfortunately his builds ran in permissive mode only, so some time ago I started to update the sources to build a version which runs in enforcing mode. Today I synced the latest sources from LineageOS and build the 20260612 version with the latest security fixes. If you are interested in installing you find the packages needed on my download area

Installation is quite easy, but a bit tricky:

• Download all needed packages
• Boot into fastboot mode and flash the following tree images
  • fastboot flash:raw kernel boot.img
  • fastboot flash:raw recovery_ramdisk recovery.img
  • fastboot flash:raw recovery_vendor recovery_vendor.img
• then disconnect you USB cable and press both Vol-+ and Power until you see the "Devcie is booting ..." message
• Now you are in LOS-Recovery and you can
  • adb sideload lineage-20.0-20260612-RELEASE-mediapadm5wifi.zip
• If you would like to install GApps, too, I suggest you to use MindTheGapps