Great to have you back!
I also never heard the term scanlation before, so here is what I could find out just now. Scanlation is well known in the manga community, meaning fans making translations using a scanner and the results getting distributed digitally, usually with permission of the artist. However, there seems to have developed a practice of not just translating but also modifying the content to a degree, just look at page 2 of the third link you posted: https://web.yongsai.net/comics/gaston-lagaffe/gaffes-and-gadgets/2
Das erste Buch ist ausreichend, mehr geht immer wenn du dann möchtest :)