Hi Concalo
If you are running frimware from Xiaomi.EU then you have to do full wipes, otherwise you would get errors updating to official MIUI.
I used to install TRWP once Xiaomi.EU release firmware version to install only from TRWP.
I recall situation where I've just intsalled MIUI official rom over Xiaomi.EU and had annoying phone process errors - IMIE was missing. In this case you just need to reset your phone through settings menu.
In summary, if you have stock bootloader and runningt Xiaomi.EU you could download MUI official firmaware and flash it through Updater.
Then after the phone is booted you have to reset it through Settings menu.
P.S. There is an easy way to install TRWP