It is understandable, due to how one of plugins works. Basically, changes made to the equipment in the engine won't change data about your equipment in already existing save files. Only removing those items and adding them again to your inventory is going to update them. That's why in pre Melissa's update saves you can equip those, because in Melissa's update Chyos made some changes alongside adding new equipment.
That's weird. Please include your save files before taking training with Liv. Gonna check it.
Oh god. I asked for a save files! NOOO!