Currently, Asus Zenfone Max M2 only stops at Android 9. And the bootloader unlock tool was also removed from the homepage by Asus, so I share how to unlock bootloader for Asus Zenfone Max M2 / Pro M2 via command line.
Unlock bootloader Asus Zenfone Max M2 / Pro M2
Download file unlock.zip
Connect device with laptop/pc via usb & enable usb debug.
Then unzip unlock.zip and run
adb reboot bootloader
cd /path/to/unlockMacOS
chmod +x unlock.sh
unlock.shWindows run unlock.cmd
Install custom ROM for Asus Zenfone Max M2
Talking about custom ROM, I immediately think of Pixel Experience ROM. This ROM is pure Google so it's as smooth as the Google Pixel ROM Download link and instructions for installing custom recovery are below