I faced the same problem described in this comment. But when I switch to terminal there is only native language available - not default, nor custom language switches works. Looks like native language is set by default. Same language problem in recovery mode when I run root shell prompt on boot.
Last thing I've tried: Loaded from installation flash and learning how to mount file system type 'crypto_LUKS'.
Any recommendations on how to remove package in such conditions would be nice!
System: Ubuntu 18.04. Lenovo E15 laptop.