Hmm...You mentioned clean flash. You wipe all the data including system, data, cache, dalvik, right? After that, you flash the miui Eu 11?
Sorry to ask so much on this because my poco works with magisk. So I was wondering is there anything trigger the boot loop. I wish I can have your poco so I can check. Lol.
I would suggest you to take o look on this XDA thread. You can ask questions here about your issues.
Xiaomi Pocophone F1 [Beryllium] WARNING: Before attempting to root your device, do note that by unlocking your bootloader and modifying your device with root, ROMs, etc... you are NOT risking voiding your warranty! I am NOT responsible for...
forum.xda-developers.com