. . . Murder in Baldur's Gate which I know almost nothing about, that supposedly deals with "Gorion's Ward" and his death. Descent into Avernus on the other hand . . . Justin Alexander's blog thealexandrian, . . . which is why I'm expecting Larian to change it a lot.
Murder in Baldur's Gate essentially finishes the story of BG1+2, with the final Baal spawn being killed off (no, it's not Abdel/Gorion's Ward ;)), and the God of Murder being reborn... it's an ok module, all things considered... a bit low level for the supposed gravitas of the subject matter.
Descent into Avernus I haven't played either, but judging for the EA alone, Larian is at least changing some of it...
I understand that this adventure module from 4e deals with the 'canon' Ward, Abdel Adrian, and Bhaal continuity, but I don't know how closely they (Larian/WotC) plan to cleave to the little known Abdel canon, similarly to how the novelizations for the games never influenced the games themselves. This is more or less the question I was asking with this thread. How many of these continuity questions have they really broached, answered or evaded?
I haven't played Descent into Avernus either, but Justin Alexander does a pretty deep dive into the module, and the print continuity around such things as Elturgard, Avernus and Zariel etc. which might as well make anyone who reads it an expert, but it seems pretty typical of what you would expect from a story by committee trying to make a easy-to-play campaign. Which is why I think it will be pretty different in BG:3, likely roping in the Mind-Flayers and the Githyanki.