I work free if they still development the game or I help the mods. when we have new artist I try to help him/her with history, I must can't avoid place my own conception of the project but I discuss with community first.
The Romans are kind placeholder specially the helmet. Boudica is mostly represent equal. a Celtic girl with an armor. in composition I prefer Bust shot.
Diadochi mostly have Alexander placeholder helmets.
In Spanish is Mauria = Maurya
https://es.wikipedia.org/wiki/Imperio_Maurya
https://en.wikipedia.org/wiki/Maurya_Empire
But the demonym is Mauryan -an adding the suffix