havard
Adventurer
There was a proto-Feywild in the Seelie Court, in that it was its own plane that wasn't quite connected to the other planes in the normal way. Of course, in 2e it was accessible from several Outer Planes (most notably the Beastlands, Arborea, and Ysgard) instead of the Material Plane, but otherwise is was fairly similar...
Mystara had its own version of the fairy world. In PC1 - Tall Tales of the Wee Folk, it was referred to as the Feywood. I have made a map of it here.
Elves OTOH are said to be the creation of the Immortal Ordana, although the Dragonlord Trilogy suggested yet another creation story for the elves of Mystara.
-Havard