What are the unit classes in that game? Did 'infantry' covers both shock troops armed with axes and swords and spearmen? or ... divided between the two??
All very good questions, but I don't think we have definitive answers yet. In the various trailers and screenshots we've seen 'infantry' armed with primitive axes, swords, spears, (apparently) pikes, bows and crossbows. We've seen mounted troops armored and unarmored, hints at knights. War elephants. We have not seen, as far as I know, any sieges or siege engines, artillery, or 'modern' weapons like tanks or artillery - but then, we've only seen a few shots of anything past the middle ages/renaissance-looking eras.
Going back to Amplitude's previous game,
Endless Legend, they differentiated troops into infantry, ranged, 'cavalry' and Flyers (it was a fantasy game, so there were some really weird graphics hiding under those definitions), and Sieges were sort of 'semi-automatic' in that siege lines appeared around a city and its districts if you moved an army next to it and 'declared' a siege. The city defenses slowly were reduced (faster if you had a much bigger besieging army than the city had defenders) until the 'fortifications' were at 0 and you could make an assault.
The actual weapons troops were equipped with, though, depended on what you 'bought' for them (and developed through Technology and acquisition of Resources to make the weapons and armor). That meant Ranged could be armed with bows, improved bows, or crossbows, 'infantry' with swords, spears, and 'cavalry' with swords, spears, etc. Armor could be bought for head, torso, legs, or separate shields.
I would dearly LOVE it if they kept this system in
Humankind!
Imagine: start being able to make weapons out of wood, bone, stone and horn, 'armor' out of leather or bone, 'shields' out of wood tor leather, get Copper or Bronze and start making Head (Helmet) and torso (cuirass) armor out of Bronze, shields faced with bronze, weapons now including short swords and axes, move on to Iron or Wrought Iron, Steel, Steel Armor Alloys, right up to modern 'Kevlar'.
Whether a unit had Anti-Cavalry capabilities or not might not depend on 'class' but on its specific weapons, some of which (spears, pikes) would have extra effect against mounted troops.
The 'Emblematic' troops might have a 'standard' suite of equipment each, like Greek Hoplites with bronze cuirass, helmet, and greaves (leg armor), shield of leather, wood and bronze, spear tipped with iron, Roman Legion with iron armor for torso and head, wood and iron shield, iron throwing spear, iron/low grade steel sword.
Of course, that kind of system would require a great deal of graphic work to distinguish troops with, say, leather versus bronze or iron/steel armor and the mass of possible weapons and materials combinations. It might, in fact, be too much to hope for, because I would expect such a system to have been Showcased o at least Hinted At by now: all of us old SMAC fans would already be drooling over our keyboards . . .