Weapon Swap Problem? Maybe

So I'm playing as a Merc, and decided to try and equip a 2nd crossbow to have a 2nd ammo always loaded to swap back and forth with. However, whenever I switch to my secondary crossbow and attack, it automatically switches back to my main hand crossbow. Not sure if this is a bug or I'm doing something wrong.

I am having the same issue. And nothing yet about that.

If a skill is set to be used with only one weapon, it'll always use that one weapon.

Maybe you're using a skill that hasn't been set to be used by the second weapon. Just guessing here