The art is pretty unmistakable. And both Cthulhu and the Great Race have D&D history as both where in the original Deities & Demigods.
So now the copywrite is gone they (and probably more Lovecraft monsters) are being put back into the game.
Forge of the Artificer has plenty of new content despite being a small book. Bastions, airships, three campaign outlines…
I don’t think the new Ravenloft book will have significant repetition beyond things being updated mechanically. I’m pretty sure new campaign outlines have already been...
Bebble & Grime box set probably contains both Arcane books.
Note: this is pretty much equivalent to how the did the Spelljammer and Planescape boxed sets, only without a slipcase.
Both are genetic. If you look at cats, their skin colour and patterning varies along with their hair. I can tell my two black cats apart because one has whiter skin whereas the other has browner skin, visible inside their ears where hair is sparse.
They could involve their expensive lawyers or give away something for free and rewrite the system reference documents.
Or they could just reprint the class.
Placeholders for species not yet updated to the 5.5 ruleset. Also, there is nothing in the FR book that requires those things in order to use it, they are just mentioned as existing in the world.
Anyway, it would be technically impossible for someone who owned the reanimator on DDB to use it...
Maybe, or maybe the psion will be in the Arcane book. I assume the artificer will be in the ravenloft book, since it features the reanimator subclass, and I think it unlikely they will say “you must own Eberron to use Ravenloft”!