Hello @ta
The voices available in the "OfflineNeural" container are the same as the voices available in the "OnlineNeural" container. The difference between the two is that the "OfflineNeural" container is designed to run on-premises, while the "OnlineNeural" container is designed to run in the cloud.
You can find a list of the voices available in the "OfflineNeural" container in the following link: https://docs.microsoft.com/en-us/azure/cognitive-services/speech-service/language-support#neural-voices1
Let me know if you have any other questions.
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