Can we please stop discussing fake out? Yes, it has limited use in singles, and is pretty great in doubles.
I'm very happy Gallade has such a great stat distribution, it really is his saving grace which will help him be viable in OU.
I'm looking for a good offensive core using M-Gallade. I'm thinking either Weavile/Bisharp, but then who else?
In this case, Rotom-W would work very well, as both Gallade and Weavile/Bisharp are very susceptible to Talonflame (and CS Landorus-T in case you are using Bisharp, although it cannot always safely switch in as it fears Ice Punch/Knock Off/Bisharp's Defiant) and the washing machine can take on the bird and double as a slow Volt-Switcher to safely bring in Gallade/Weavile/whatever.
Speaking of cores, after testing my offensive core some more, I'd say Gallade works well with
CB Scizor too; Scizor has powerful priority as well, it can beat Fairies more reliabily than Bisharp (It can actually switch in on Pixelate Hyper Voice/Moonblast while Bisharp struggles doing so, and it's also a better check to Mega Gardevoir, which I'm kinda weak to), while it can also grab momentum with U-turn and Pursuit-trap the likes of the Latis and Gengar; Gallade, on the other hand, sets up without much problem on the things that trouble Scizor (Ex.: Zapdos) and can tank at least one special move aimed at the mantis.
The core has some problems with MegaMence (which is why I added Unaware Clefable, although it's still 2HKOed by Return X_X) but who doesn't have problems with that
broken af thing? :P