Usage metric reports can't be downloaded to a PBIX file.
Datasets modified by using the XMLA endpoint can't be downloaded to a PBIX file.
If you create a Power BI report based on a dataset in one workspace and publish to a different workspace, you and your users won't be able to download it. The download feature is not supported in this scenario.
You can only download the original report. You can't download a copy of a report.
Based on the above posts, you can also refer to this similar thread: