I've set up an additional accessory slot called 'Weapon Attachments'. I wanted these to be accessories that could add elemental attributes and other things to your weapons, but *facepalm* they give you defensive bonuses instead. I know, I'm stupid.
I thought maybe giving the items in question auto-states with the right elements would work instead but blarg, those are defensive as well.
Is there a way to change this up so that it'd work as I intend it to?
What are you like at scripting? You could make a mod to the attack_effect routine in the Game_Battler3 script to allow for accessories to modify a weapon's power/elemental attributes. You'd probably also have to do something to stop the defensive effect of the accessories too.
I can't really help you with your query, sorry, but I do have a suggestion with your name "weapon attachments", maybe "augmentations" sounds a little more interesting? You could then use the items for armor if you so chose and don't have to change the name, plus what they ultimately do is augment your equipment rather than just attach ;)