yoi, the Euro factions could made the M2 southern european portaits. Their diplomats will use RTW greek diplomat portaits, and their spy/assassins got Roman rogue portaits.
In the other hands, I think the Melayu FM could use M2 middle eastern merchants and diplomat portaits (note : melayu FM got M2 middle eastern portaits of merchants and diplomats - just need to get them some destar and kain, while some could still use their turban). The diplomats and rogues will use eastern FM without helmets (Jebivjetar-ish portaits made wearing destar).
The Java-Sundanese FM will use modified eastern FM portaits, as well as several Armoured M2 middle eastern portaits, we'll got them with both helmets and not, but we could add some proper headgear too (imagine Jebivjetar portait wearing Blangkon, or Iket), the rogues and diplomats will be the same with Melayu.