Firaxis has used the ballcourt as a wild card building for both Mayans and Aztec, but, I would be thrilled if the Olmecs got it, they invented the darn thing after all.Honestly the Ballcourt was everywhere in mesoamerica, if we have no Olmecs I'd rather it was just the base mesoamerican look of whatever the "culture" building is
There's plenty of options for the Aztecs, as you mention, Chinampa is a must, Calmecac or Telpochcalli, Tzompantli (skull rack).
Personally I'd like to see Chinampa and Telpochcalli or Calmecac (they were both schools divided by class), and having both being able to upgrade to Calpulli unique district, it's just so flavourfull.
Yes Zapotec had their golden age in what would be Antiquity civ, they were later conquered / incorporated into the Mixtecs, which would be exploration. I think a good way to think about Antiquity and Exploration age civs for mesoamerican would be, before and after Teotihuacan.
The thing with the Olmecs is, there's a reason they are often called the "mother culture" for mesoamerica, they pretty much put in place the bases for most cultures that came after. So civic wise there's planty to choose from (and we only need 3), , the 260 days ritual calendar, veneration of the feathered snake, ritual bloodletting, the aforementioned ballgame, etc.
I can see however how even with civ 7 particular freedoms doing the Olmecs could be rather difficult, as opposed to other classical mesoamerican civs, like Zapotecs or Teotihuacan. I hope Firaxis gives it a try tho.
