Honestly, outside of Equestria, Sunset is just a girl with some empathy and telepathy powers sometimes. She’d probably get fucking hardcore wasted since she doesn’t have ki training and otherwise she’d just have the body of a teenage girl. If she had access to her Unicorn magic she MIGHT last a little bit? DBZ regularly throws out guys who are on the level of PLANET BUSTERS, and no one in Equestria is really geared towards fighting.
 
Though I mean she CAN be determined, so she might train? Maybe? She’d need the right kind of motivation. Actually, hmm.
 
Okay, it’d all boil down to WHEN Sunset ends up in the DB universe. Anything later than the Frieza Saga and she’s just a bystander. Let’s start close to the beginning of the Saiyan Saga. Maybe a little before.
 
Bulma finds a weird statue with strange readings and has it taken back to Capsule Corp to study. A few nights later, Sunset stumbles out and finds Bulma. One thing leads to another and Bulma wants Sunset to stick around so she can run some tests. Sunset doesn’t mind and she doesn’t seem like she wants to go back through anyway.
 
In fact, Sunset seems a kinda bitter about what happened on the other side and it takes Bulma a good bit of nagging before she finally gets Sunset to open up and say that she comes from a land of magical talking ponies. Sunset’s caught off guard when Bulma takes the whole thing in stride by saying she’s “seen some pretty crazy stuff.”
 
Sunset becomes interested in technology, Bulma’s impressed with Sunset’s drive and ability to pick stuff up quickly, and she ends up as Bulma’s assistant for the time being. Sunset isn’t exactly a genius on the level of Bulma and she ends up being mainly a gofer for grabbing tools for her, but the setup lets her get more acclimated to the world and it keeps her mind off of home.
 
Obviously the Saiyan Saga has to start sometime, so Bulma heads out to Master Roshi’s and Sunset tags along. She meets the crew and everyone has different levels of interest in where she comes from, with Goku just asks if there’s any strong fighters in Equestria and Sunset saying that it doesn’t really work like that there. Goku kinda just waves the place off after that.
 
Raditz shows up, that shit goes down about the same. Sunset ends up finding out about the Dragon Balls and ends up thinking that maybe she could use them to get back at Celestia, but that idea gets thrown out the window after Goku dies and Piccolo takes Gohan.
 
It’s around this time that she learns about ki. “Wait, so it’s kind of like magic?” And those are the secret words. It’d probably be a tossup whether she decides to stay with Bulma or try to find out if she can actually tap into ki. I’m not sure if she’d go with Krillin somehow to Kami’s or stay with Roshi? Though I mean, Roshi’s kinda… weird, and Bulma has probably already told her some things.
 
Considering that Fighting is Magic in DBZ, Sunset MIGHT end up taking to it. If she doesn’t, she’d end up with Bulma and possibly learn technology. She’d probably never get the chance to actually make a wish with the Dragon Balls considering everything that goes on, but if she did, it’d probably be at a period of time after she mellows out and no longer holds a grudge against Celestia, so she might try wishing for her Equestrian magic? I wonder if that would work.