rate my team

Metagrose mega
Zen head-butt
Hammer arm
Cant remember rest right now
Or if I don't use that I use
Tyranitar mega
Sand storm
Crunch
Outrage
Earthquake

Blaziken mega
Flare blitz
Sky uppercut
Brave bird
Rock smash

Greninja
Subsitute
Smokescreen
Water pulse
Toxic spikes

Breloom
Drain punch
Sky uppercut
Poison powder
Seed bomb

Venomoth
Sleep powder
Signal beam
The physic type move that does exactly the same as signal beam
Poison fang

Gardevoir
Moon blast
Psychic
Future sight
Magical leaf

Can you post their nature and what evs you placed in them please

In addition to the above comment-

I'd pull together your full planned moveset for mega Metagross first, but you will probably want Bullet Punch on it.
Also, Rock Smash is a waste of a move on Blaziken, plus you already have fighting-type coverage in Sky Uppercut. Try Thunder Punch or Rock Slide maybe?
Smokescreen is also a waste, and Substitute is probably not a good idea on Greninja as it isn't defensive enough to take a hit.
With Breloom, I'd replace Drain Punch with Mach Punch, and if you want it to have recovery, give it black sludge with the Poison Heal ability.
Venomoth, Poison Fang is useless on it due to its lackluster attack- give it Sludge Bomb, which is a special attack.

This isn't really a full team (Just post the team you want to use) since there are 3 megas on the team, also there is literally no point in giving a Tyranitar sandstorm since it will anyways set up sand with its entry.

Yeah tyranitar just had sandstorm because I hadn't replaced yet