Who are the Dark Eight in 1492 DR (Forgotten Realms' Dalereckoning)?
I'm currently preparing a campaign section that will involve an ambitious devil that is preparing to climb the ranks and their way into the Dark Eight and am tied to the timeline.
Do we know if they are still Baalzephon, Corin, Dagos, Furcas, Pearza, Zaebos, Zapan and Zimimar?
There is no reason to believe that they would be different. Baalzephon, Corin, Dagos, Furcas, Pearza, Zaebos, Zapan and Zimimar were mentioned in the 2e Planescape sourcebook Faces of Evil: the Fiends (page 29), which got published in 1997. The same names appear on page 36 of the 3.5e sourcebook Fiendish Codex II: Tyrants of the Nine Hells (FC2:TotNH), published in 2006.
FC2:TotNH also offers a reason why they have been the same for millenia and will keep on being that way: these pit fiends are not really immortals, they die regularly enough. However, when one dies, some other fiend takes on its mantle and reshapes to appear like it. This creates the illusion that the generals of the Blood War are unbeatable commanders.
Chris Perkins (principle narrative designer for 5e) discusses the Dark Eight at the Dragon Talk: Lore You Should Know episode on April 19, 2019. At around 6 minutes 40 seconds into the video, Perkins mentions Baalzephon, Zimimar, Zaebos, Furcas, and Corin by name, though it is clear that he does not remember all their names. Furthermore, he adds that he hopes a new one will get introduced in the future. Yet, based on the use of future tense and the casual tone of the conversation, it is not clear whether and when such a modification to the lore will indeed happen.
