Do Triarii get the mount bonus so they do not get a penalty for fighting against infantry.

If the intro to the unit desc file is correct


; stat_pri_attr
; primary weapon attributes any or all of
; ap = armour piercing. Only counts half of target's armour
; bp = body piercing. Missile can pass through men and hit those behind
; spear = Used for long spears. Gives bonuses fighting cavalry, and penalties against infantry
; long_pike = Use very long pikes. Phalanx capable units only
; short_pike = Use shorter than normal spears. Phalanx capable units only
; prec = Missile weapon is only thrown just before charging into combat
; thrown = The missile type if thrown rather than fired
; launching = attack may throw target men into the air
; area = attack affects an area, not just one man

then phalanx units don't get mount effect cause they get hidden bouses and penalties from having "phalanx", Triarii do not form phalanx so shouldn't get a penalty when fighting infantry but cause they have spears they need a bonus against cavalry.

Armenian infantry if they can for phalanx and get mount bonuses are way out there, I have no idea about that