Priyanka and Sophie are hanging in South Beach with Nick and Joe Jonas, and the future sisters-in-law are getting in on the spring break action with some super cute swimwear ... doing their best to upstage The Jonas Brothers' music video shoot.

Priyanka is absolutely killing it in her tiny black bikini ... and Sophie is showing off her figure in a black and yellow checkerboard one-piece. Talk about bringing the heat!

Nick, Joe and Kevin in pastels are cool ... but we gotta give this round to the ladies.

Nick's wife showed why she's an absolute badass ... hopping on a waverunner and blowing through the bay. Joe's fiancee kept it chill on the yacht -- she's more of a sit around and chug wine kinda gal.