They stopped support because many devices got bricked. You won't have fastboot, you won't have anything in such cases. Only Boot ROM download mode, which requires a Mi Authorized Account. In such cases, you will need to visit a service center.
I think you can't install xaomi Eu rom but you can install various rom which are available simply by flashing through twrp
once you have unlocked you bootloader and installed twrp it must be easy flash any rom
I think you can't install xaomi Eu rom but you can install various rom which are available simply by flashing through twrp
once you have unlocked you bootloader and installed twrp it must be easy flash any rom