Some questions about swords, AP, and unit list vs ablilties at a glance

[athanaric]

I don't know what unit list you are referring to, but here is a general overview:

All falxes, clubs, maces, axes, hammers, two-handed swords, underhand cavalry lances, kopis/falcata swords, elephant tusks, sling bullets, artillery projectiles, soliferra, and pila are AP, which is of course the same as "effective against armour".

Keltoi long swords are not AP. Skordiskoi swords are not AP; additionally they have a low lethality (.12), but a decent attack. Cordinau Orca are renowned for their armour and general martial prowess, not for special AP attributes.
Kopis/falcata swords as wielded by many Iberian and Hellenic units are AP (unlike most other swords) but have a low lethality (.11).

The falx-like sica "swords" wielded by some Dacian units are not AP; they have a normal lethality (.13).

Apeleutheroi are not AP, they are useless.

If a unit has a ranged precursor attack, the AP attribute of the melee weapon will not appear in the unit description, even if the javelin itself is AP (as is the case with Asturian or Rhaetic Axemen).

Pezoi Brettioi have AP pila but a normal sword.