Windows 10 Print to PDF from command-line

问题

I'm correcting assignments from my students right now and I'd like to automate an annoying step I always have to do.
After annotating their PDF solutions, I need to Print them to PDF files in order to bake my annotations into the PDF so that they can be included in LaTeX. Right now I have to manually choose "Microsoft Print to PDF" and enter the PDFs name with a leading underscore (which is what my automatically generated LaTeX files expect). This gets annoying for 30+ files.
So I'd like to issue this in a batch-script automatically for all the PDFs to minimize my efforts to a simple double-click. I have seen that this is possible with e.g. C# (Here), but I'd like a solution with a simple batch script.
Can this be done?

Edit:
The C#-Code I found actually does not get the Job done. You can't print existing PDFs that way. I'd need to use Spire.PDF to do that. The Free Version however messes up the PDF; I can download the "Full" version in NuGet, this however generates a disclaimer at the beginning of any PDF, and it still can't handle things I draw in Adobe Reader DC. So C# really is not an option, I need a command-line solution.