I just want to say I'm very happy to have found this plugin. For my game, I was wanting a skill system where each Character had their core skills, but were able to learn additional skills by using "Skill Cards". But, they have to Equip them and can only have so many equipped at a time out of their pool of "Skill Card Skills".
With this plugin, I set my Skill Card items to teach the Passive Skill, which then in turn applies a State that actually teaches the "Active" Skill. This results in exactly what I was looking for, so thank you!
I do have an Enhancement Request: Instead of my situation above (Setting a State which teaches an Active Skill), can you allow Passive Skills to recognize the "Learn Skill" Trait in addition to the "Add State" Trait? That would bypass me having to create states for each skill. (I'll look into coding a patch on my own, but if you have time/want to, it would be appreciated!