You should be able to use COM interoperability , specifically the OpenAsDocument() and Save() methods. You can also use COM interoperability to read from Excel, but using ImprtFrom-CSV would be much easier. Then you just iterate over the file names, and for each one open the template as a document, then save it as the filename.

I haven’t tried this Switch port, but the new engine that launched with this update really improved the frame rate, especially at the end of a run. I went from barely double digit fps to a mostly steady 60 on my Steam Deck.