IANAL, but EU law doesn't have "fair use". It does have a _very specific_ set of uses where you don't have to ask for permission (or pay). As I understand, it is more limited than the US' "fair use" doctrine.

EU being EU, I can only imagine there's a bunch of particular rules around research that may or may not work in the authors' favor.

Fair Use is Copyright and has a four factor test. Trademark is different than Copyright. Perhaps learning the difference might be educational…and fiscally prudent.

Fair Use != Fair use

https://www.inta.org/fact-sheets/fair-use-of-trademarks-inte...