Stir together cornmeal, parsley, chives, tarragon, baking powder, salt, and pepper in a medium bowl. Add milk and egg; stir until well combined. Fold in chopped shrimp. Beat egg white with an electric mixer on high speed until soft peaks form; gently fold egg white into cornmeal mixture. Set aside.
Pour oil to a depth of 1/4 inch in a 10-inch cast-iron skillet. Heat over medium-high until hot. Carefully drop tablespoonfuls of batter, in batches, into hot oil; cook until golden brown, 2 to 3 minutes per side. Transfer to a wire rack on a rimmed baking sheet to drain; keep warm in a 200°F oven until ready to serve.
Sprinkle fritters with chopped herbs. Serve with Mustard-Lime Sauce.