Oh yeah its Pachirisu time. Used this team almost exclusively post baile ban to get to 2nd on the ladder.
Anyway, I can't remember why I opted for Pachirisu, other than funny and my prior teams had struggled with electrics.

Excellent speed tier and not-awful bulk lets it come in and harass strong enemy threats, primarily oricorios which aren't ground or electric. Also very useful for locking strong threats like crab into resisted moves, allowed for momentum to swing back.

physical breaker. you click facade, things die, wahoo.

probably the star of the team. most games you will be aiming to clean with this, as well as it being your tera target. First Impression is so good on it and has saved me in many many games. No Retreating and then switching out makes me almost briefly like tera a tiny bit.

surprisingly bulky, mainly used as a slow pivot into breakers or falinks as well as rocker. Just fairly solid overall for chunking stuff.

opted for a bulkier oricorio as on this team as its main purpose is removal. not having a flying move does sting sometimes, mainly with other oricorio, but I find the other moves are too important to give up on. Ground is for both offensive and defensive purposes, as its surprsigly common for teams to be able by just ground rev dance alone. Might want to invest some speed in for certain things, like maybe lycanroc and falinks

special breaker, click moves, things die. wahoo. Speed tier is super duper nice so the likes of haunter. Both tera fire and normal are fine.
Goal of the team is basically pivot around to get int breakers, opening up for either falinks or oricorio to clean, with pachirisu stopping scary opposition.
90% of the time it'll be either oricorio or falinks who tera. I've occassionally terad Billy and Pyroar, never terad perrserker or pachi
3 main threats:

/

this is just not good on my end, they do kinda run you over a bit. Against Dug, generally I lead tera Billy and try remove it asap.
Wugtrio I've just been very lucky not to go up against often.

really chunks everythig, even pachi. If its scarfed then its managable with Pachi pivoting. Specs is just difficult to maneuver around, you'll most likely be taking one mon falling when dealing with it

not really a threat as much of an annoyance. Only answer for this it really keeping up pressure and chunking it with normal stabs.
Hope you have fun with it :))