Love your plugin.
However, I noticed that it conflicts with two notetags in VisuMZ_1_ItemsEquipsCore: <Added EType: x> and <Added ETypes: x, y, z>.
Your plugin will cause these two notetags to not work at all. I just wanted to let you know.
Thanks for the report.
Unfortunately, because of the obfuscation of their code, there's no way for me to know what they're doing with that note tag, or how I managed to break it. Does the tag not work entirely or only on shields? It could be that the Shield slot doesn't count as an armor slot for their plugin anymore when you're dual wielding, because it would normally be a weapon slot. It could also be that the modification I made to force unequip items from the offhand when equipping a two handed weapon, or when a main hand weapon disallows a specific wtype in the offhand simply overwrite some change they'd already made to that function.
You can try moving around the plugin load order, but I don't think that will help, unfortunately.