Is it still possible to relock the bootloader at Mi9 with IodeOS? If “yes” how can I do it?
No, neither with iodeOS nor any other CustomROM is it possible to relock the bootloader of the Mi9 again.
The Xiaomi Mi A2 is the only Xiaomi smartphone where a Verified Boot Re-Locked Bootloader has been realized with a specially made CustomROM so far.
OK, thank you for the answer.