A bit late to the party, but I wanted to throw out a kinda gimmicky set I've been having fun with.
Malamar @ Focus Sash
Ability: Contrary
Nature: Jolly (+Spd, -Sp. Atk)
EV: 252 Spd, 252 Atk, 2 HP
Moves
-Topsy-Turvy
A must on any anti-meta Malamar build for obvious reasons. Ruins a setup sweeper's day. If they manage to get outspeed you and get a good hit, focus sash enables you to still pull this off.
-Destiny Bond/Switcheroo
Odd I'm not seeing the former more often on Malamar builds, but I suppose that's a good thing, it gives it the element of surprise. Egg move off of Qwilfish. Malamar is a pretty weak Pokemon compared to the common meta, so this with the focus sash lets you, at the very least, kamikaze a potential threat. Of course, this'll only be an option for Mons you can outspeed, and even with EV training Malamar can easily be topped by a niche sweeper.
The latter is obviously useful, and fun to get off after you've burned your focus sash to take the opponent's item with it.
-Foul Play
This is is great, great, great against physical sweepers that don't resist dark. Because it takes into account your own stat changes, it gets STAB, and it won't be nerfed by a Topsy-Turvey on Swords Dance/Dragon Dance either.
-Superpower
Pretty obvious inclusion on a Malamar build. Great with contrary, and the stat boosts stack with Foul Play, letting you boost off of a sweeper's attack.