In a small microwave-safe bowl, heat 4 tablespoons lime juice on high until very hot, about 1 minute. Add onion, pressing into juice to completely submerge; let cool completely. Drain.
In a 12-inch cast-iron skillet, heat 2 tablespoons oil over high heat. Add corn; cook, without stirring, for 3 minutes. Stir, and cook 2 minutes more. Remove from skillet, and transfer to a large bowl.
Add remaining 1 tablespoon oil to skillet. Add okra; cook, stirring frequently, until just beginning to brown, about 2 minutes. Remove from skillet, and transfer to bowl with corn. Stir in onion, jalapeño, cilantro, feta, sugar, salt, pepper, and remaining 3 tablespoons lime juice. Garnish with cilantro and feta, if desired.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/corn-okra-salad/