In JIRA priorities are translated.
In eazyBI priorities are not translated. Language is set to german.
Unfortunately, eazyBI won’t translate values for members from standard fields.
You can try creating calculated members (with german names) already in eazyBI UI in the “Priority” dimension and then create references in formulas to imported (English) members.
Then select new calculated members in reports.
Martins / eazyBI support