It's possible to go back to Nougat in ZE520KL without using ADB/AsusFlashTool/FastBoot method?Installing 15.0410.1712.31 on ZE520KL
The ROM is for ZE552KL, but with a few steps you can install it on ZE520KL!
YOU'LL NEED AN UNLOCKED BOOTLOADER!
- Flash a stock Nougat recovery from ZE552KL (you can find it here)
- Go to the recovery and Wipe Data/Factory Reset and Wipe Cache (you'll lose everything)
- Install WW-14.2020.1712.85 for ZE552KL
- Let the Zenfone 3 boot for the first time. After that, reboot to recovery again and install 15.0410.1712.31 (Oreo)
Nougat installation will take 2-3 minutes
Oreo installation will take 10 or more minutes
GETTING BACK TO NOUGAT