>>183832171. A lot of those Pokemon are really good in Doubles, Escavalier is a pretty commonly used Pokemon and likely even more so now due to Knock-Off/Overcoat buff and Megahorn. Just because they're not OU in Singles doesn't mean they're ranked the same in Doubles, just look at Cress.
2. Some of those were in older formats, where Pokemon usage was restricted. Musharna was incredibly common in Gen V the first year, because the format was limited to only Gen V Pokemon. As soon as that restriction was lifted, it was replaced by Cresselia who does just about everything better.
