For the dipping sauce: In a small bowl, stir together the ponzu, hot sauce and stir-fry seasoning.
For the wontons: In a bowl, add the chicken, scallions and stir-fry seasoning. Mix with a spoon until well combined.
Put a wonton wrapper onto your work surface. (Keep the wonton wrappers covered with a damp towel so they don't dry out.) Place 1 heaping teaspoon chicken mixture in the center of the wrapper. Coat the edges of the wrapper with a little water using your finger or a brush. Fold the circle to form a half moon, pressing out any air bubbles Set aside, covered with a damp towel, while you make the rest.
When you are ready to cook, place a large, nonstick skillet fitted with a lid over medium-high heat and add the vegetable oil. When the oil is hot, place the wontons in a single layer in the pan; they should be close together but not touching. Depending on the size of the skillet, you may need to cook the dumplings off in 2 or 3 batches. Cook, uncovered, until the bottoms are browned, about 4 minutes. Lower the heat to medium-low, carefully pour in 2 tablespoons water and immediately cover the pan with a lid. Cook until the wontons are tender, about 5 minutes. Remove from the pan and serve hot with the dipping sauce.