Overview
My goal here was to build a fast, frail offensive team that didn't completely buckle under Trick Room. Necrozma uses Electric Seed in tandem with Calm Mind to form a bulky standoff wincon that also hits respectably hard and helps clear opposing Steel-types. Ferrothorn and Torkoal form a bulky backbone that punishes most Trick Room teams for trying to set it.
Salamence
This is just standard mixed-attacking Salamence with Fire Blast > Hyper Voice. Fire Blast OHKOs Mega Metagross if you set sun with Torkoal, and it essentially becomes a "fake STAB" for Salamence.
Tapu Koko
Basic stuff.
Necrozma
I wrote a pretty lengthy post recently that explains how EVs for Electric Seed Necrozma work, so if you want to know more about those
read here.
That said, the basic idea here is to use an Electric Seed, in tandem with Calm Mind, to become a bulky juggernaut that fires off strong attacks and recover as needed. Under sunlight, Necrozma can recover 75% of its health using Moonlight, and again Heat Wave becomes like a "fake STAB."
Deoxys-A
Psychium-Z is the wave, so I just used that. Electrium is probably ok here too if you want to use that instead. Don't bother with Focus Sash though; a good opponent's going to see the Salamence and Torkoal and set Stealth Rock on you anyway.
Ferrothorn
Obligatory Rain check and defensive backbone. I went with Toxic > Leech Seed to punish Snorlax and other bulky stuff. Knock Off works here too.
Torkoal
Secondary rain / weather check, as well as a Trick Room check. Torkoal can live a Stakataka Stone Edge and retaliate with Earth Power, and also speed tie Camerupt to try to get an EP off on it as well. It's not the sturdiest Camerupt check, but Camerupt can't OHKO Ferrothorn, Torkoal and Necrozma in one move so you should always have at least something to hit it with.