>>17979595It's fast enough to always have a Destiny Bond up against most foes with Prankster (including Azumarill's Aqua Jet with a little bit of investment), and slow enough with Phantom Force off that great neutral coverage, 165 base Attack that you'll always either be able to get a kill in most every match, whether it's by DBond being up for effectively two opponent's turns or PForce's damage.
Prankster Will-o-wisp means opponents can't use it as setup bait (not that perma-DBond + Phantom Force is setup bait either) and allows for it to support the team in any stage of the match.
You can't even Magic Bounce it to oblivion, like Bounce does with all the other non-Foul Play Pranksters (and bulky Xatu deals with Foul Play mons a lot better than Espeon could hope to).
They did try, and I feel that M-Banette is fairly balanced, with some strong unique niches (breaking at worst 1 for 1 is hardly bad, considering even M-Blaziken can't do that in a meta with Talonflame) but with clear limitations to prevent it from being OP.
>>17979577First turn vulnerability is legitimately bad, and severe 4MSS is never good (though I feel it isn't so bad in the case of M-Banette, who doesn't need to worry about coverage since it's not sweeping/getting KOs because of strong coverage, it's just choosing which large subset of mons you want to effectively hard counter), but I feel that it doesn't make M-Banette 'pretty awful.' If you're comparing it other megas with respect to sweeping potential, then sure, it's on the lower end of the mega spectrum, but it doesn't make it an awful mon overall.