Deploying on Jira instance with different language
With CMJ you can deploy snapshots on Jira instances with a language different from that on the source instance.
Below you can find some specifics that you should have in mind when doing this.
Different language for configuration objects on source and target
CMJ matches most of the objects by their name as this is the only way to do this in an instance independent manner. This means that if a configuration object is named in one language on source and in another on target instance, then CMJ will not be able to identify this object as the same during the deployment and will mark the object from source as a new one in the diff page.
CMJ provides functionalities to resolve such problems via selectively modifying the changes during the diff phase. You can read more here: Selective Merge
You can also rename the objects on source to match their name on target and create the snapshot anew.
Object translations
Some of the configuration objects (custom fields, issue types, statuses, etc) allow adding translations and CMJ is able to migrate them together with the object itself.