When exporting portfolio plans to Powerpoint, the portfolio data is produced but there is no data in the Project sections. This is true for OOTB and for templates we have created.
So I don't know if this is similar but I was working on the Export to PowerPoint plugin on a custom app and ran into the same issue. For me, the MS Add-in for the export app was not working so I just did freehand for the data elements (like ${project_status.project}. No data was populating in my PPTX so after some digging into the out of box templates I found that the data tags, which I assume came from the MS Add-in, had included a hyperlink on the closing bracket of }. So I tested by adding in the hyperlink (which is https://servicenow.com/distinctionFlag=base/relatedTo=none) on JUST that closing bracking and lo and behold, data is now populating on my custom template.
