There are quite a few Weapon / Shield / Bow Ornaments that have the wrong Item Information on them. Example the Buckler / Shield Ornaments (Air, Earth, Fire, Ice & Prismatic) sold by the Supply vendors in Dragonscale Hills. In both forms (as a Container... or after converting them to a Slot 20) they say they are for 2H Slash Weapons, when they are, in fact, for Shields only. Other such ornaments -- quite a few in fact -- also have the same / similar concerns (Item Information does not match the Ornament Restriction).
Maybe this has to do with the "Charm Effect" data? That seems to be where the error is (a category seen on Zam that has the erroneous info).