Need natures and EVs of these Pokemon for a better analysis.
Empoleon
Ability: Torrent
Item: Wise Glasses
Hydro Pump
Ice Beam
Flash Cannon
Signal Beam
Empoleon doesn't do well as a straightforward sweeper because his offensive movepool is so limited. He's better relegated to things like the SubPetaya strategy - give him a Petaya Berry, Substitute, and Agility, switch in on something Empoleon resists (and because of his typing, that's a lot), use Agility on the switch, and use Substitute until you hit 25% health, at which point the Petaya Berry will kick in along with Torrent, allowing you to pull off an amazing late-game sweep.
But if you really want to use this kind of Empoleon, I'd suggest you drop Hydro Pump for Surf. A miss can easily mean death. Replace Signal Beam with Grass Knot, it provides much better type coverage and power. Wise Glasses isn't a great item, so I'd go with Life Orb or even Leftovers instead.
Zapdos
Ability: Pressure
Item: Focus Sash
Thunder
Charge
Ominous Wind
Heat Wave
I'm... not really sure what this Zapdos is meant to do. Is it defensive or offensive?
If it's offensive, Heat Wave looks good. Charge and Thunder are both useless - Thunder's accuracy is terrible, and Charge just gives the opponent another turn to beat on you. Replace Thunder with Thunderbolt. Ominous Wind is terrible. It's too weak, and the stat boost is rare. Find somewhere to put Roost on this set so you can heal when you need to, and find out what this thing's Hidden Power type is. If it's Grass or Ice, great, use it. If not... well, Zapdos doesn't have a lot of options. Signal Beam is the only one I can think of that's not a complete waste, and even that's a pathetic option.
If it's defensive, pretty much everything I just said still applies. You might want to drop Heat Wave for Roar to force out anything trying to boost on you, or replace Hidden Power/Signal Beam with Reflect or Light Screen, but overall they're pretty similar.
Like sres said, Focus Sash is wasted on Pokemon like Zapdos. Use Leftovers or Life Orb instead.
Shuckle
Ability: Gluttony
Item: Undecided
Rock Slide
Toxic
Power Swap <-- Do you mean Power Trick? I'm pretty sure Shuckle can't learn Power Swap.
???-(Forgot)
The ability on Shuckle really doesn't matter, but if you're battling over WiFi, then Sturdy would probably be a better option in case some jerkoff decides to pull a Horn Drill on you.
Rock Slide and Toxic look good, but Power Trick is a serious problem. Power Trick Shuckle is a gimmick at best. In double battles it could work, with liberal use of Follow Me and a ridiculously bulky Clefable, but in single battles it fails instantly. Shuckle may have astronomical Attack after using it, but it also has paper-thin Defense, and no matter what the situation, you're going to be screwed over. Shuckle's speed is the lowest in the game, so you'll be crushed flat before you can pull off a single attack. Drop it for Knock Off. Protect is a viable option to stall for Toxic damage, but Stealth Rock is a nice move that your team happens to be missing.
Leftovers is the item for this set - there's pretty much no other option.
Gallade
Ability: Steadfast
Item: Muscle Band
Psycho Cut
Brick Break
Leaf Blade
Aerial Ace
Replace the Muscle Band with either a Choice Scarf or a Choice Band - Scarf for speed, Band for pure power. Replace Brick Break with Close Combat, and Leaf Blade for Ice Punch. If you decide to run a Choice Band set, replace Aerial Ace with Shadow Sneak; if you're using a Scarf, use Night Slash.
Blaziken
Ability: Blaze
Item: Undecided
Blaze Kick
Sky Uppercut
Shadow Claw
Thunderpunch
Blaziken is too slow to pull off an effective sweep without any sort of boost. Either give him a Choice Scarf or replace Shadow Claw with Agility. I'd also suggest dropped Sky Uppercut for Superpower.
Blissey
Ability: Serene Grace
Item: Focus Sash
Endeavor
Softboiled
Charge Beam
Psychic
Hoo boy. First off, there is no point in having a Focus Sash on something as bulky as Blissey. Drop it for Leftovers. Next, Endeavor is terrible on Blissey. Her Attack is terrible, and it'll be pathetically weak even with the status effect boost. Softboiled is good. Charge Beam... eh. I suppose it could work, but you'd probably be better off with either Toxic or Seismic Toss. Psychic isn't a good attacking type unless it has STAB, so drop it for Ice Beam. Serene Grace is workable with your current set, particularly in conjunction with Charge Beam, but Natural Cure's probably the better option since Blissey's inevitably going to get hit with Toxic, and being able to clear that away is a nice ability to have.