Unlocked units XDA thread: https://forum.xda-developers.com/t/opn100-oos-83ba-unbrick-tool-to-restore-your-device-to-oxygenos.4217855/

Specific notes:

Crossflashing regional builds is no longer possible by EDL, flash is tied to device project ID. For reference EU devices project ID is 20883 while international devices project ID is 20881.

T-Mobile variant XDA thread: https://forum.xda-developers.com/t/opn100-oos-tmo-be82cb-unbrick-tool-to-restore-your-device-to-oxygenos.4245495/

Metro by T-Mobile variant XDA thread: https://forum.xda-developers.com/t/opn100-oos-metro-be82cf-unbrick-tool-to-restore-your-device-to-oxygenos.4245499/