Xiaomi Mi A2 - TrebleDroid/treble_experimentations GitHub Wiki
Xiaomi Mi A2 Android 9.0 Pie GSI Tutorial
https://forum.xda-developers.com/mi-a2/how-to/guide-install-android-9-0-pie-aosp-gsi-t3832694
https://forum.xda-developers.com/mi-a2/how-to/guide-install-android-9-0-pie-aosp-gsi-t3832694