Mark of The Black Hand
Long before the Valnari Empire, These elves were part of the Summer and Winter courts and some grew tired of the constant infighting and left for Aedir. Those that remained in the feywild are known as the Eladrin.
Same as the Eladrin in the DMG.
Valnari (High Elves)
The Valnari or the High Elves once ruled most of the known world, but that empire has long since fallen.The Valnari elves are mostly scattered across the lands and only a few city states remain.
Same as High Elf in the PHB.
Saelyr (Wood Elf)
The wood elves are the descendants the Alorin elves who held to the ancient traditions of nature worship. Their small communities exist throughout the forests of the world. The Largest of these is in the Saelyn Reaches.
Same as Wood Elf in the PHB.
Eldyr (Dark Elves)
The Dark Elves split from their cousins long ago in an ancient conflict known as the Sundering. Their hatred of all religions and other races has branded them as evil throughout the world. They hail from the nightmarish land known as the Eldraith Nightmoors.
Same as base Elf race in the PHB. With the following subtype:
Ability Score Increase. Your Strength Score increases by 1.
Elf Weapon Training. You have proficiency with the Longsword, Shortsword, shortbow, and longbow.
Eldyr Magic. You know the blade ward cantrip. When you reach 3rd level, you can cast the hex spell once per day. When you reach 5th level, you can also cast the ray of enfeeblement spell once per day. Charisma is your spellcasting ability for these spells.
Another of the Elven cultures that split during the Sundering. This particular sect was driven underground due to their devotion to the demon goddess Lolth. They are extremely rare on the surface world though rumors of raids throughout the north speak dark skinned elves.
Same as Drow in the PHB.