>>23021725That's not it at all. In fact Eviolite taking your item slot makes Chansey significantly worse in Ubers than Chansey.
The whole point is that despite things like Moon and Leaf Stones existing, GF doesn't make Eevee evolve into Umbreon or Leafeon using them because they existed before and despite making logical sense, won't cause item inconsistency. So they're gonna stay away from "why can they suddenly use eviolite on Carbink this is bullshit" or even go back to gen 6, put eviolite on Carbink, and ask why it's not working.
