I have this issue too with both French and Italian.
However, if you select “Display tips below the Attachment block” that text is correctly rendered in the right language!
Sounds like a path is being created incorrectly (except the above exception) so the mo files are not being found.
I do have my wordpress directory in a different directory than the site. Maybe this is an issue?
Could someone with better coding skills and/or knowledge of the code have a look and help Prince09d and me, please?
Thanks
Alastair