Four new custom fields

As base for using Jira's built-in automation and reporting functionality, the app provides a custom field that stores the customer language "Customer Language" for every support case in your service desk.
It is determined at the first customer request.

You can get three more custom fields when you enable the experimental features language sentiment and key phrases: "Initial Sentiment""Last Sentiment" and "Key Phrases".
They are not available by default.

Four Use Cases

1. Reassigning issues based on the customer language

If you have native speakers of a language in your service desk team, it might be of value to add this language as "agent language" in settings and let them handle the conversations in this language,
rather than automatically translating them. With the built-in automation feature you can reassign an incoming request after the Jira Service Desk Language Tools determined the language of the request.
On Jira Cloud and Server you can also use another plugin for that, like the free "Automation Lite for Jira", which is more flexible than the Jira built-in one:
Automation for Jira - Cloud Lite
Automation for Jira - Server Lite

The following screencast shows how to create an automation rule for reassigning issues based on the customer language. 
The server version misses the automation trigger "Time in Status".  So you will need another app for this task.

Cloud: Screencast-Assigning Issues.mp4 Server: Screencast-Assigning Issues (Server).mp4

2. Creating a queue for a specific language

Alternatively you can also easily create a service desk queue, based on the language detection feature of Jira Service Desk Language Tools:
one queue for incoming German requests, one for Spanish, etc.

Following screencast shows how to do this.

Cloud: Screencast-Create a Language Specific Queue.mp4 Server: Screencast-Create a Language Specific Queue (Server).mp4

3. Sending an E-Mail-Notification on the use of rarely used languages

For some rarely used languages that you want to monitor, you can use an automation rule to send you an alert email is someone uses it.

In the following example we use the Automation Lite for Jira app for cloud. If you don't have it yet, you can get it on the market place. It's free.
Unfortunately for server the trigger that we use in this example is a PRO feature. You can try it for 4 weeks.

Cloud: Screencast-E-Mail on Baltic Language use.mp4 Server: Screencast-E-Mail on Baltic Language usage (Server).mp4

4. Escalating a service request with low language sentiment (experimental)

Using the Microsoft Azure language analytics the app provides you with a language sentiment on each customer request and the following responses.
Language sentiment comes with a value between 0 and 100 where 0 is worst and 100 is best.

We recommend to experiment with this feature, if it the results are meaningful in your environment, as we made the experience that this is not always the case.
Anyway, when you want to use this feature, you have to switch in on in the app settings of the project.

Then you can do things like this:

Cloud: Screencast-Escalate On Low Sentiment.mp4 Server: Screencast-Escalate On Low Sentiment (Server).mp4