On PS4, we have access to content that isn’t even supposed to be in the game yet. Specifically, we have access to Insignia’s, such as Insignia of Ymir, Insignia of Set, and others. I have looked on the Wiki and these items are not yet implemented into the game.
Some of them are items no longer in use, some are RP items. Some do stuff. XD
I wouldnt worry about it, left over items is pretty common thing. Could be like older patches that left you with 0.00 weight no named item, with no icon that couldn’t be move in any form. Always taking up a slot were it was. =/