Hello. Using ArcGIS Pro 2.9, but same behaviour on ArcGIS Pro 2.8.x. Windows 10 Pro.
If I print a layout with no map series, the frame I have made is nicely centered on the paper. If that same layout uses a map series, then the layout margins seem to change and the frame gets clipped off. The frame seems to get pushed up a bit and right quite a bit. Same behaviour printing to a Ricoh PCL6 Business machine and to an HP T2600 PS plotter.
In the attached PDF of a scan of my paper prints, the grey line to the far right is a scanner artifact.
Exporting to PDF does not have this issue. Bug??
We are currently investigating a similar, if not the same, issue. It sounds like you have a work around by exporting to PDF and then printing from the PDF.
If this is an issue that you wish to track I would highly recommend logging this issue with support. They are better equipped to handle troubleshooting steps and gather bug data. This could be important if your usecase is different than the one currently being investigated. They can be contacted at https://support.esri.com/en/contact-tech-support.
Thanks for the feedback.