Fyi: Another way to deal with Perish Song is running Soundproof on one of your 'mons. It's quite niche, though...
Night (Oricorio-Sensu) (F) @ Weakness Policy
Ability: Delta Stream
Shiny: Yes
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe
Brave Nature
- Metronome
Starry (Oricorio-Pom-Pom) (F) @ Lum Berry
Ability: Soundproof
Shiny: Yes
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe
Jolly Nature
- Metronome
^ This was my first Mets team, and, uh, yea. I wanted to play around with Oricorios, and I ended up, after a LOT of trial and error, with this team. Night's Delta Stream really helps out with sfx (super-effective, I say sfx in my head) hits, and WP makes it really hurt if it gets hit by an sfx move. Also, Ghost typing is quite good because of all the Normal type moves bouncing around, and, to a lesser extent, Fighting. Starry has textbook Soundproof to deal with mothertrucking Perish Song and I had no idea what item to give it but when in doubt, Lum Berry.