NPC's aren't limited in weapon choices to job types.

There's an NPC in the MCH questline that uses a 1 handed axe paired with their gun.

The leader NPC in Limsa with the name I can't spell uses 2 guns.

Rauhban used 2 1 handed swords until things happened causing him to have less than 2 hands.

There might be more but these 3 came to mind immediately.