The Settlers IV: History Edition does include Community Pack though (fan-created single-player campaigns). "Im Namen des Konigs" is in fact from a different publisher but it was authorized by Sunflowers. Similar situation to The Settlers IV, that's why I was hopeful. Thanks for clearing it up.
I am not involved with Settlers, so I can't speak to what happened there, but Settlers IV was published by Ubisoft itself back in the day, so maybe that made things legally and licensing-wise easier for their History Edition.
These projects can be quite legally tricky unfortunately, as things were quite different back then than they are today.