I'd love to use Specs or Scarf Latios in this kind of metagame. With the exception of Tyranitar, it's dangerous against pretty much everything, especially when you lure Metagross | Gardevoir | Diancie | Scizor, making your teambuilding more flexible for some specific purposes (like getting free Spikes with Ferrothorn or Skarmory without hesitating against some random Fire | Fight coverage, or helping CM Clefable breaking its checks on the long run). Azumarill should be a bit dangerous, although you can play around it moderately well with Regen Grass-types or Rotom-Wash. Weavile is an interesting case, you can't use use Scizor as your failsafe (or Lopunny to pivot around the resisted Knock Off), but on the flipside, people should use Azumarill | Keldeo more often than usual to counterplay it. Yes, it's a great buff for Weavile, i don't see it getting overpowered. I don't think it influences Chansey's usage overall, it's just a convenient buff for choiced Lati@s and Thundurus.