Preheat oven to 500°F.
Mix ground turkey, panko, egg, salt, scallions, ginger, cilantro, 1 tbsp soy sauce, and 2 tsp oil and mix with your hands until combined well. Shape 1/4 cup meat mixture into a ball and transfer to a baking dish that has been sprayed with cooking spray. Repeat with remaining mixture. Bake until cooked through, about 15 minutes.
For the dipping sauce mix together lime juice, water, soy sauce, and remaining 1 teaspoon of oil in a bowl. Add scallions.
Transfer meatballs to a serving dish. Stir sauce, then drizzle meatballs with 1 tablespoon sauce.
Serve meatballs with remaining sauce, about 1 tbsp per person. You probably won't use all the dipping sauce.