Unable to export Test Plan field when Jira´s Default language is German

Description
Unable to export Test Plan field when Jira´s Default language is German

How to reproduce

1. Create a template with the following mapping for Test Plan issue

   ${Test Plan} 
   ${Testplan} 
   ${cf[customfield_id]} 
   

2. Change Jira´s Default Language to German
3. Go to a Test Execution created from a Test Plan with the Test Plan field
   
4. Export the template

Actual result/Attachments
The template is empty

Expected result
It should export the mapping

Workaround
Using Xray´s Document Generator, we´re able to export the translated Test Plan field using any of the mappings:
${Test Plan}
${Testplan}
${cf[customfield_id]}