Sorry in advance, I don't know all the achievemnt and faction names in English, so I am describing or guessing.
Yesterday, I took Rome as Nuraghian Confederation by winning both battles - but automatically.
In response to that, I got the achievement "Upgrade all buildings to lvl6 in the Etruscan capital", but not the one for taking Rome as not-Roman faction.
Is that a known bug?
Kind of unrelated: As I played Total War: Warhammer II, I got the achievement "Family Feud" while playing the Empire (it's a Tomb Kings faction achievement). Do they have trouble with achievement prerequisites? x3