could be funny, maybe the souls inside the dropped soul orb would flicker on and off like a broken lightbulb to signify it's a fake, but otherwise look identical
i think an item like this could be a viable 3.2k to be honest, i would limit it to tech damage instances too so guns arent too impacted as they already have a wide variety of counters
really really large modifiers are stuff that probably should be avoided, stuff like "+50% Spirit Damage", "+135% Healing Effectiveness", ect are really scarily large numbers even if they have downsides
it isnt that an item who's only counter is useless, but instead that only being able to counter an item by buying that item is bad gameplay design and incredibly frustrating to experience as a player because it forces you down specific build routes instead of letting you do what you want which...