I don't know how Qwilfish fares in X/Y, tbh. Tentacruel is the better option over it, IMO, as it can Rapid Spin to clear away your entry hazards:
-Scald
-Sludge Bomb
-Rapid Spin
-Knock Off/Toxic
Nature: Bold
EVs: 252 HP/224 Def/32 Spe
Item: Black Sludge
Ability: Liquid Ooze
One of the reasons why Qwilfish was good in RU last generation was because of Intimidate, which compensates for its so-so bulk. Without it, it falls to physical attacks even with investment. If you insist on keeping Qwilfish, this is the set to use; Waterfall is a better mono-attacking type than Poison because Steel is immune to Poison:
-Spikes
-Pain Split
-Waterfall
-Thunder Wave/Taunt/Haze
Nature: Impish
EVs: 252 HP/240 Def/16 Spe
Item: Black Sludge
Ability: Intimidate
One of Garchomp's strongest moves is Earthquake, and you're not taking advantage of it; it's currently walled by Steels without it; also, Earthquake hits Fairies hard enough already. Goodra, Druddigon, Mega Ampharos and Zygarde do the bulky Dragon role better. If Garchomp is to use Stealth Rock, this is the best way to do it:
-Stealth Rock
-Outrage/Dragon Claw
-Earthquake
-Fire Blast/Swords Dance
Nature: Naive/Jolly
EVs: 252 Atk/4 SAtk/252 Spe
Item: Lum Berry/Focus Sash
Goodra:
-Draco Meteor
-Fire Blast
-Thunderbolt/Sludge Bomb
-Focus Blast/Dragon Tail
Nature: Modest/Quiet/Sassy
EVs: 248 HP/252 SAtk/8 SDef
Item: Leftovers/Assault Vest
Ability: Gooey/Sap Sipper
or
-Dragon Pulse
-Flamethrower
-Thunderbolt
-Toxic/Dragon Tail
Nature: Calm
EVs: 248 HP/8 Def/252 SDef
Item: Leftovers
Ability: Gooey/Sap Sipper
Druddigon:
-Stealth Rock
-Outrage/Dragon Claw
-Earthquake
-Sucker Punch
Nature: Adamant
EVs: 236 HP/252 Atk/20 Spe
Item: Leftovers
Ability: Rough Skin
or
-Outrage
-Dragon Claw
-Sucker Punch/Fire Punch
-Earthquake/Superpower
Nature: Adamant
EVs: 236 HP/252 Atk/20 Spe
Item: Choice Band
Ability: Rough Skin
or
-Outrage/Dragon Claw
-Flamethrower
-Earthquake
-Sucker Punch/Substitute
Nature: Lonely
EVs: 216 HP/252 Atk/20 SAtk/20 Spe
Item: Life Orb
Ability: Sheer Force
or
-Glare
-Dragon Tail
-Stealth Rock/Rest
-Earthquake/Sleep Talk
Nature: Careful
EVs: 252 HP/4 Def/252 SDef
Item: Leftovers
Ability: Rough Skin
Mega Ampharos:
-Volt Switch
-Dragon Pulse
-Rest
-Sleep Talk
Nature: Modest
EVs: 252 HP/44 SAtk/192 SDef/20 Spe
Item: Ampharosite
Ability: Static
or
-Volt Switch
-Dragon Pulse
-Focus Blast
-Thunderbolt/Heal Bell
Nature: Modest
EVs: 236 HP/252 SAtk/20 Spe
Item: Ampharosite
Ability: Static
Zygarde:
-Coil
-Earthquake
-Dragon Tail
-Substitute
Nature: Careful
EVs: 252 HP/4 Def/252 SDef
Item: Leftovers
or
-Dragon Dance
-Outrage
-Earthquake
-Stone Edge/Extreme Speed
Nature: Adamant
EVs: 64 HP/252 SAtk/192 Spe
Item: Life Orb/Lum Berry
or
-Coil
-Earthquake
-Stone Edge/Extreme Speed
-Rest
Nature: Adamant
EVs: 56 HP/252 Atk/200 Spe
Item: Chesto Berry
or
-Glare
-Dragon Tail
-Earthquake
-Substitute
Nature: Impish
EVs: 188 HP/252 Def/68 SDef
Item: Leftovers
Clefable has recovery in the form of Moonlight and Softboiled. Use them:
-Calm Mind
-Moonblast
-Wish/Softboiled/Moonlight
-Protect/Flamethrower
Nature: Bold
EVs: 252 HP/244 Def/12 Spe
Item: Leftovers
Ability: Unaware/Magic Guard
or
-Wish/Softboiled/Moonlight
-Moonblast
-Protect/Flamethrower
-Aromatherapy/Toxic
Nature: Bold/Calm
EVs: 252 HP/244 Def/12 Spe (Bold) or 252 HP/244 SDef/12 Spe
Item: Leftovers
Ability: Unaware/Magic Guard
or
-Moonblast
-Fire Blast
-Thunderbolt
-Softboiled/Moonlight
Nature: Modest
EVs: 244 HP/252 SAtk/12 Spe
Item: Life Orb
Ability: Magic Guard
While Gallade is my favorite Pokemon, it doesn't fare well in OU because anything it can do, Lucario and other Fighting Pokemon can do better:
-Nasty Plot
-Aura Sphere
-Flash Cannon
-Shadow Ball/Dark Pulse/Vacuum Wave
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Lucarionite
or
-Swords Dance
-Close Combat
-Extreme Speed/Bullet Punch
-Crunch/Shadow Claw/Ice Punch
Nature: Jolly
EVs: 4 HP/252 Atk/252 Spe
Item: Life Orb/Lucarionite
While Blaze Kick seems tempting on Genesect, it only sees use on physically-based sets. Here are much better options for it:
-U-turn
-Ice Beam
-Flamethrower
-Bug Buzz/Thunderbolt
Nature: Hasty/Naive
EVs: 4 Atk/252 SAtk/252 Spe
Item: Choice Scarf/Expert Belt/Life Orb/Focus Sash
or
-Shift Gear
-Iron Head
-Extreme Speed
-Blaze Kick/X-Scissor
Nature: Hasty
EVs: 24 HP/252 SAtk/8 SDef/224 Spe
Item: Life Orb
or
-U-turn
-Iron Head
-Extreme Speed
-Flamethrower/Ice Beam
Nature: Hasty
EVs: 252 Atk/4 SAtk/252 Spe
Item: Choice Band
or
-U-turn
-Iron Head
-Ice Beam
-Explosion
Nature: Hasty/Naive
EVs: 252 Atk/4 SAtk/252 Spe
Item: Choice Scarf
Genesect has a tendency of switching around back and forth, which can make entry hazards (and/or Life Orb recoil take its toll on it), so Rapid Spinner or Defog users are appreciated to control the entry hazards on your field. I suggested Tentacruel, but if you don't like it, here are some more suggestions for you:
Excadrill:
-Earthquake
-Rock Slide/Iron Head
-Rapid Spin
-Swords Dance/Stealth Rock
Nature: Jolly
EVs: 4 HP/252 Atk/252 Spe
Item: Life Orb/Air Balloon/Chople Berry
Ability: Mold Breaker
Starmie:
-Hydro Pump/Surf
-Thunderbolt/Psyshock
-Ice Beam
-Rapid Spin
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Leftovers/Life Orb
Ability: Natural Cure
or
-Scald
-Rapid Spin
-Psyshock/Ice Beam/Thunderbolt
-Recover
Nature: Timid
EVs: 248 HP/32 Def/4 SAtk/224 Spe
Item: Leftovers
Ability: Natural Cure
Blastoise:
-Water Pulse/Scald/Hydro Pump
-Dark Pulse
-Aura Sphere/Ice Beam
-Rapid Spin
Nature: Modest
EVs: 252 HP/252 SAtk/4 SDef
Item: Blastoisinite
Crobat:
-Brave Bird
-Roost
-Defog
-Taunt/Toxic
Nature: Jolly
EVs: 168 HP/136 Atk/4 SDef/200 Spe
Item: Black Sludge
Ability: Infiltrator
Mandibuzz:
-Foul Play
-Roost
-Taunt/Whirlwind
-Defog/Toxic/Knock Off
Nature: Bold/Impish
EVs: 248 HP/216 Def/44 SDef
Item: Leftovers
Ability: Overcoat
