There is only a workaround at moment for using encryption on Mi 8 with xiaomi.eu:
https://xiaomi.eu/community/threads/mi8-force-encryption.45691/
I can confirm the above method is working with the latest weekly version.
Thanks for the tutorial. What is the security patch level for EU Stable ROM (10.0.6.0) because mine is still 2018.08.01 as it was on global 10.0.2.0 ROM?