Leader - Montezuma I - This is a special edition for those who preorder, but it unlocks for everyone 90 days after official release.
National Ability - Aztecs can use their builders to rush construction of Districts.
Leader Ability - Gifts for the Tlatoani - Luxuries give amenities to extra cities, each individual luxury gives additional military power.
Unique Unit - Eagle Warrior - Replaces the standard warrior, but can turn defeated enemies (But not Barbarians!) into Builder units.
Unique Infrastructure - Tlachtli - In the Entertainment District. Gives amenities, faith, and Great General Points.
I CAN'T SPELL SHIT YO.
It's a really expansionist civ. My guess is that you pump Eagle Warriors, and then invade your immediate rivals. You use these in order to build up districts, so that your cities become powerhouses. You also make sure that your enemies have the luxuries you don't have, so that you can be more powerful as you attack your next target.
IN A SPECIAL BONUS EDITION:
New Wonder! - Huey Teocalli
This wonder probably gives a ton of faith, as it was the place where Aztecs did their blood sacrifice.
Estoy el el móvil y no puedo traducir sin suicidarme en el intento, mañana lo pongo bonito.