I had to flash a chinese ROM via EDL, now it is working again. Never touching xiaomi.eu-roms again.
Here is more information. But you do not need to physically open the phone. You can go into EDL mode via "fastboot oem edl"...
Tried with "flash_all_except_storage.bat", rebooted into fastboot again.
Tried manually flashing with your commands...."hyp.mbn" does not even exist in the rom you linked.
I did flash the xiaomi.eu-rom from this post. Followed the instructions exactly and used the windows_fastboot_first_install_with_data_format.bat. Since then I am in fastboot loop.
I tried to flash older xiaomi.eu-versions afterwards, tried the official global and chinese versions. Everything...
fastboot boot boot.img
Sending 'boot.img' (196608 KB) FAILED (remote: 'failed to check sparse crc')
fastboot: error: Command failed
This was boot.img from the venus_images_V12.0.22.0.RKBCNXM_20210206.0000.00_11.0_cn
I am having the exact same errors. Tried with the provided scripts, tried with MiFlash, tried with XiaoMiTool V2, tried from different terminals in Windows and Linux. Phone stays in "Fastboot-Loop".
Seems like it can't correctly build the "userdata"-partition:
.\fastboot.exe continue
Resuming...