Na, in der alten Welt kam das Chaos ja erst in grauer Vorzeit durch die Old Slann auf die Welt, weil die an den Polkappen rumgedocktert haben. Vorher gab es kein Chaos in der Alten Welt, wohl aber die Elfen, wenn mich nicht alles täuscht.
Im Umkehrschluss bedeutet dies vllt. , dass die Elfen (die noch kein Chaos kannten) nicht wirklich mit den Eldar verwandt sind (wenn diese Slaanesh erschufen) ODER aus den Eldar hervorgingen, als diese noch kein Chaos kannten (?kenne mich mit den 40k Eldar nicht aus?).
So oder so sind das imho zwei unterschiedliche Universen mit ihren eigenen Zeitlinien, auch wenn es so viele Überschneidungen gibt.
Hier noch ein Fandom-Fund:
"In earlier editions of both Warhammer Fantasy and Warhammer 40,000, there were many indications that the Warhammer World, the planet that is the primary setting for Warhammer Fantasy, was located in the same universe as Warhammer 40,000.
In later editions of both games, Games Workshop moved to create more of a separation between the two fictional universes, although they have also never completely denied the earlier connections between the two settings.
In the original conceptions of both properties it was likely that the Warhammer World did exist in the same universe as Warhammer 40,000 as the Warhammer World is known to have been terraformed and reshaped by beings known as the Old Ones, essentially the same alien entities as the Old Ones of the Warhammer 40,000 universe.
The Warhammer World's continents are arranged very similarly to those of Earth and may be an indicator that the Old Ones also played some role in shaping the Earth and affecting the development of Humanity in general several million years ago, after their supposed disappearance from the galaxy.
Other worlds in the Warhammer 40,000 universe have been discovered by the Imperium of Man that also have been terraformed into a shape reminiscent of Earth's distinctive continents.
In this conception it is possible that the Humans of the Warhammer World were settlers who first arrived on the planet many millennia ago during the Dark Age of Technology and then reverted to a primitive state as so many Human populations did across the galaxy during the Age of Strife, while the Elf and Dwarf populations were beings shaped by the Old Ones from Aeldari and Squat stock, respectively.
Finally, in this conception, the Greenskins (Orcs and Goblins) of the Warhammer World were clearly a type of Feral Ork.
The forces of Chaos are even more active on the Warhammer World than they are on many other planets of the galaxy because of the collapsed Warp Gates the Old Ones built on the planet, devices that are very similar in function to the Aeldari's Webway technology, which was itself derived from the Old Ones' knowledge of the Immaterium.
These damaged Warp portals have allowed the Warp to manifest fully at the north and south poles of the Warhammer World, essentially creating two small Warp rifts at both ends of the planet similar to the Eye of Terror which spew Chaos energies directly into the physical universe, creating what the inhabitants of the Warhammer World call the "Winds of Magic."
Because Chaos can manifest its forces directly on this world, its Elf, Dwarf and Human defenders of Order were slowly but inexorably losing their battle with the Ruinous Powers, ultimately culminating in the Warhammer World's End Times.
Following the destruction of the Warhammer World in the End Times and the birth of the Mortal Realms of the follow-on property of Warhammer: Age of Sigmar, it is now clear that in current lore, the universes of Warhammer 40,000 and Warhammer and Warhammer: Age of Sigmar exist in entirely separate realities.
All that unites them at present is the existence of Chaos and the Realm of Chaos, which is functionally identical between both universes. "