If you are an admin in Zendesk you can change the language settings. Clicking the gear icon in the app will open up settings for incoming messages:
Adding / deleting languages to the "Don't translate from these languages" will prevent Transfluent for Zendesk app from translating messages and posting those as internal notes.
If you are an experienced Zendesk admin, you can also do changes to the trigger which sends the incoming messages for translation. After you have installed the app it will create a webhook and a trigger, which sends the incoming message for translation. You make changes to the trigger launching conditions in the Zendesk admin settings.
The trigger is named "[Transfluent integration] - incoming ticket translation" and it should not be deleted, or no incoming messages will be translated. Also note that if you want to delete the app, you must also uninstall the trigger.
The default settings for the trigger are: