I have installed the recovery.img (included in e-1.18-t-20231228-UNOFFICIAL-begonia.zip by @ronnz98) via fastboot flash recovery recovery.img. The reboot did not go into the e-Recovery, but resulted in a bootloop with the MI logo. Since I switched off my ‘begonia’, it no longer starts. The screen remains black. It is massively bricked.
@ronnz98, I am well aware of the risks when I install a CustomROM, especially an untested one. But - no risk no fun. In the meantime I was able to revive the ‘begonia’.
No @smu44, anyway thanks. I felt like I had made 1000 attempts by trying various instructions from the WWW. All of them failed because the different versions of MTK-bypass Utilities (Auth Bypass SLA/DDA) did not work.
After what felt like 1001 attempts, I was finally able to unbrick my ‘begonia’ with the help of Python + MTK Client + SP_Flash_Tool + Stock Android 9.0. The upgrades to the latest version Stock Android 11.0 are still ongoing because the Xiaomi servers have been working extremely slowly for days.