My only preferred set after qualifying and bothering to lose enough with Kyurem-B to try it out (lol):
252 spatk / 252 speed hasty
Yea, that's 0 atk evs and -def nature and no outrage...I used this solely to set up my other sweepers and I hated losing it early game when locked into an outrage. I just used this to lower Jirachi / Ferro (using EP and FB respectively) for Double Dance Thund-t and doing things like switching it into Politoed / Tenta (and praying for no Burn fuck Scald and fuck Gamefreak for making that terrible move) and then playing mind games with the opponent cause he knew something was getting hurt.
Again, sole purpose was to punch small holes in opposition to let my Thund-t set up...iirc the only things that can take this are WoW Jellicent / Mew / Sableye...and no fucking Jellicent is staying in on this unless it knows it doesn't have Fusion Bolt lol, so the first time I play someone I'm ok. Even Sableye is hurt by Ice Beam though so as long as you have some way to handle bulky Mew (hello Genesect), you should be good.
I know people have been really making a big deal of Kyurem-B's outrages but...lol, as an offensive player (in a notably offensive metagame), sacrificing something to take out something isn't a "liability," it's literally expected every single game. When I see opposing Kyurem-B outrage, I jump for joy, cause it just means I sac something and take out Kyu-B easily. I'd honestly recommend not using Outrage that much in a meta as offensive as this (as counterintuitive as that may sound)...
Even though I didn't use the Sub set much, I'd say the sets that scare me the most are Sub sets and 4 attack (non outrage) sets cause both put the onus on me as a player to make the best move or get wrecked by Kyurem-B (who also doesn't have nearly as bad a movepool as the other side has been claiming it does).