Those who want a custom ROM for their Xiaomi Mi A1 close to Google's stock offering will probably enjoy ShapeShiftOS. For me, the lack of OTA updating, the stability issues that I bumped into, as well as the rather basic customization options make this piece of code unusable as a daily driver.
https://www.notebookcheck.net/Android-11-on-the-Xiaomi-Mi-A1-via-ShapeShiftOS-A-lackluster-near-stock-experience.517739.0.html