its through weapon unleash yes, however said skill is VERY similar to the base attack, its just under a different name. (Instead of "Attack" its called "Shoot")
[here is the one without the Action Sequence stuff that still has the issue when its assigned to a two-handed weapon]

Here's the other one, still very much the same but it strikes all targets (i've assigned this one to shotguns) & has the action sequence stuff attached (I did this due to a problem i was facing last month where it would individually strike each and every target individually rather than all at once, and as I've stated, its only applied to shotguns)


I should note that i've tried mostly everything i could think of in regards to attempting to fix it, including just putting both Mainhand & Twohanded Tags, also after taking these images, i replaced the weapon skill plugin note tag with a weapon unleash notetag and its still attacking twice somehow, (also i am just learning i can attach more than one image, whoops! sorry for the multiple replies! I will update this one to include the multiple replies i made)
Also! Here is the plugin list in its entirety (it uploaded backwards..)! + Plugin Itself


(i tried adding in some of the extra plugins the DualWield Plugin had compatability, hoping that would resolve the issue, it sadly did not)(UPDATE, i used another weapon that is assigned to the very first skill, which i then renamed back to "Attack" to see if it has something to do with the name, still attacks twice, what did i do to cause this bug to come back??? I'm honestly flabbergasted at myself because i feel like this is inadvertently my fault and i dont know how)

Something else i would also like to clarify is that the dual wield weapons are using the same notetag, so its not interchanging notetags with one another, in fact, i had to acutally alter this a while ago and remove a couple of weapons because i couldn't get them to behave like RPG Maker 2003's Weapons nor could I locate a proper solution)