I tried a few things and one did the trick! I had an old TWRP to flash the new rom but with that twrp I was stuck in fastboot loop. I installed the latest official twrp just to boot into system and that worked!
Mi 9SE here, flashed the latest weekly over the last weeks version. Now I'm stuck in Fastboot loop. Any known fix for that issue? I did as stated on first page with boot into recovery from fastboot + tried to boot into system in recovery. No luck