I would put real links in an appendix, with refs that jump there in the online version but are simply text [xxx] or [n] in the hard copy. That does not call for much LaTeX magic. Ask at tex SE for help if you need it.

The ability to jump back to the text after viewing a reference in the appendix would be nice. That does call for a little magic.

I find footnotes distracting. Avoid them unless your discipline embraces them.

I would put real links in an appendix, with refs that jump there in the online version but are simply text in the hard copy. That's [xxx] or [n] in the body and [\url{...}] in the appendix. That does not call for much LaTeX magic. Ask at tex SE for help if you need it.

Be sure to annotate links with a "last visited" date.

The ability to jump back to the text after viewing a reference in the appendix would be nice. That does call for a little magic.

I find footnotes distracting. Avoid them unless your discipline embraces them.