Total War: ROME II - Emperor Edition

Total War: ROME II - Emperor Edition

Para Bellum - Collection
Field artillery available for the Celts, Germans or Iberian
Hey. Is field artillery available for the Celts, Germans or Iberian factions in the campaign, e.g. ballista? It is available in custom battles, but not in the campaign. Research unlocked, building built e.g. carpenter, and artillery units are not available. They are not included in the building's description either. Is it planned in the mod that not all factions have artillery available in the campaign?