Hello @Yaşar Sazak , Thank you again for your time and patience throughout this issue.
Currently the only supported languages are those listed in the language support page. Unfortunately, we don't have any further details of the support of the cultural variants of Swiss German at this moment to share with you. Will let you know if PG has any roadmap on this.
In this case, custom translator is going to be the best option for you to try and see if that helps: https://learn.microsoft.com/en-us/azure/ai-services/translator/custom-translator/overview
I hope you understand.
Regards,
Vasavi
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