I mean you can dual wield any two weapons in ER, you just don’t get special attacks where you’re using both at the same time if they’re not of the same category. This is true of DS2, also. Not every single weapon combo gives you the power stance attacks (though it does have a lot and it’s not limited to the same category).

This is one thing I actually quite loved about Lords of the Fallen over Fromsoft’s games: everything combos together, and everything can be dual wielded with two hand animations. You want a dagger and a heavy fuck off hammer? You got it!