Hi @Max Greetings! Welcome to Microsoft Q&A forum. Thank you for posting this question here.
I could not find any out of the box solution provided by the Azure Kinect DK SDK to convert the JSON data to bhv file format. This is a not a feature we support.
However, I see third party SDKs available on GitHub that can achieve this. Here are a couple of resources I have found to help you with this.
Here is a list of joint tracking hierarchy supported by Azure Kinect DK - Joint Hierarchy. You can try to extend the solution from the first GitHub repository to extend to this 32 joint skeleton data structure and get the desired result.
Hope this helps!
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