Your team has three weaknesses to ghost types and only one immunity to ghost. Aegislash would make short work of your team, and Gengar would probably too. Your team also has two dark weaknesses, and no resistances to dark. Bisharp could run through your team, and Hydreigon wouldn't have too much trouble either. Even though Gallade has a fighting type move, there's this calculation: 252+ Atk Life Orb Bisharp Sucker Punch vs. 4 HP / 0 Def Gallade: 134-160 (93 - 111.1%) -- 62.5% chance to OHKO. I don't think your team can take on most common leads and most pokemon in the metagame well.
You can use this website to further explore type weaknesses for any team: http://www.teammagma.net/teambuilder/
Another problem is that you have no pokemon faster than positive natured base 100 speed pokemon, which is a speed tier most teams aim to be above with their pokemon. You'll often give your opponent free KOs and turns.
Emolga's stats are simply not good enough. Emolga should be replaced with Zapdos or Thundurus-I. Once you get good enough at team building you can experiment with less used pokemon.
Sablyeye and Jellicent are a bit redundant since they are both ghost types with similar move pools.
Once Mega-Metagross is dealt with, Sylveon and Mega Gardevoir would sweep your team. By the way your Mega-Metagross only needs 180 Spe EVs to outspeed adamant base 100 speed pokemon. IMO you would be better off with a standard jolly spread.
I also notice your team doesn't have protect on a single pokemon. I'm guessing you are new to VGC, so protect may seem like a wasted move slot. Protect is very important for several reasons: - It helps you stall out turns of tailwind, trick room, rain, etc. - You could potentially stall out a pokemon that is about to faint from burn, poison, or weather. - You can protect your pokemon from a threat and have your partner take it out. This way your pokemon is preserved for another round. - You can predict what your opponent is going to do and use that to your advanatge by protecting a pokemon from crippling damage or status, and then using your other pokemon to get free set up or damage in. - You can bait out Aegislash in blade form, stall out sucker punch, etc.
I'm not sure what the items are on your pokemon since you didn't share them.
Quite frankly your team looks like you just threw six pokemon together without thinking too much about team synergy. Look at teams on nugget bridge and build around a core that has good switch in synergy, or around a specific pokemon or team idea.
I didn't mean to be brutal, but I figure you want to get out of the 1500 rating on battle spot or 1100 rating on showdown.
Here's how I would modify your team: - Mega-Metagross - Jolly, 4HP/252Atk/252Spe, Iron Head, Zen Headbutt, whatever you want, Protect - Thundurus-I, Bold, 252HP/140 Def/68SpA/4SDef/44Spe, Thunderbolt, Thunder Wave, Hidden Power Ice, Taunt/Swagger - Jellicent, spread is okay, sitrus berry or other bulky item, Scald, Will-o-Wisp, Recover, Shadow Ball - Instead of Gallade use Conkeldurr or Terrakion. You already have phsychic coverage, and you don't need a pokemon weak to ghost or susceptible to dark types. - Sableye is too similar to Jellicent. Landorus-Therian is always good so I'd try that. Jolly, 4 HP, 252 Atk, 252 Spe, Life Orb, Earthquake, Rock Slide, Superpower, Protect - Porygon-Z, choice scarf, Timid, 4 HP/252 SpA/252Spe, Tri-Attack, Ice Beam, Thunderbolt, Shadow Ball.
I tried to preserve some of your team members so the above team is far from perfect.