Mix 1 tablespoon of the Peruvian Seasoning, 1/4 teaspoon of the salt, 3 tablespoons of the lime juice and oil in small bowl. Reserve 2 tablespoons of the marinade. Set aside. Place shrimp in large resealable bag. Add remaining marinade to bag; turn to coat well. Refrigerate 30 minutes.
Remove shrimp from marinade. Discard any remaining marinade. Place shrimp on skewers or in grill pan. Grill shrimp over medium heat 2 to 3 minutes per side or just until shrimp turn pink, brushing with reserved marinade. Remove shrimp from skewers and allow to cool completely. Cut into bite size pieces.
Mix remaining 1 tablespoon Seasoning, 1/2 teaspoon salt, 3 tablespoons lime juice and orange juice in large bowl. Add shrimp, watermelon, cilantro, red onion, mint and jalapeño. Toss to coat well. Cover. Refrigerate at least 15 minutes before serving to allow flavors to blend.