Actually thinking about it, Jinx has better weapons, she definitely has the advantage in ranged combat.
Both of them are juiced on superhuman serums so we can assume they are physically equal, but Harley has a lot of experience in hand to hand combat plus being a former Olympic grade gymnast plus actually carrying melee weapons so melee should be on her favor.
And Harley has was more feats.
If there is prep time and Jinx gets to make her drone swarm then Jinx wins, no question. But I random encounter? Depends way to much on the details of the encounter.
No prep time.
Going off past battles Jinx will probably have a mix of her game gear and what she had in Arcane.
So Pow-Pow the minigun, Zap the hand gun (spark and/or bullet variant), Fishbones the Rocket Launcher (we will likely see the Super Mega Death Rocket), her Chomper Grenades and her Shimmer enhancements.
No idea if they would recreate the Firelight Bomb Swarm.
Saw a post elsewhere about the fight and a person claimed Jinx is nothing without her guns. -.-