I'm glad to hear that your issue has been resolved. And thanks for sharing the solution, which might be beneficial to other community members reading this thread as a solution. Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others ", I'll repost your solution in case you'd like to accept the answer.
Question: 'No items found' for 'Utterances Primary Language' when trying to create a conversation project.
Solution: It seems that the first time I went into the Language Studio I clicked somewhere and didn't get the pop up filled in to choose my Language Resource, so even though I was went to Settings and Switched resource (to different ones) it only populates the list of languages if I select the resource through the dialog box, not through settings.
If you encounter any issues in the future, don't hesitate to reach out to the community forum for assistance. Thank you.
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