linux and windows
- libreoffice - exporting pdfs allows password setting (so in combination with opening a pdf in libreoffice first might be an option)
- qpdf - password entry via command line unfortunate -- some versions allow entry via prompt (but exposed?)
windows
- pdfencrypt - source exists, but not available via scoop
- pdf-exchange-reader - no source
- ms office - word
- https://www.businessinsider.com/guides/tech/insert-pdf-into-word - "How to insert a PDF into a Word document as on object"
- https://pureinfotech.com/password-protect-pdf-microsoft-word/ - can only do "user" password, not "owner"
- What Is a PDF Owner Password?
- What Is a Document Open Password? - about "PDF user passwords"