Is publishing paper containing information acquired from sites such as Sci-Hub illegal?
I think you need to consult a lawyer for this, but it isn't the publishing that is illegal, per se. How you acquired certain information might have legal implications, and how you quote and cite might have ethical implications, of course. But both of those are independent of publishing.
Republishing copyright material is illegal in a lot of places, but I don't think that is exactly what you mean. Such republishing is illegal even if you obtain the original properly.
Answering such questions here is, however, a down vote magnet for some reason, so I hesitate to say more.
I will note, however, that copyright violation is almost entirely a civil matter. If you infringe someones copyright it is up to them to try to defend their rights via a lawsuit. And, then, they have to notice it, of course. There are some exceptions to this general rule, of course, and Disney would like to have anyone abusing their &quot;Mickey Mouse&quot; copyright thrown in jail until the copyright expires and which they also work to extend to infinity. Good luck with that.