To season the shrimp, on a plate, add the shrimp and sprinkle in the salt. Add the white pepper, then mix to coat evenly.
To make the batter and combine, in a bowl, whisk together the cornstarch, salt, baking powder, and baking soda. Add the egg white and cold club soda, then mix into a light batter. Add the shrimp and parsley, then toss to coat evenly.
To fry the shrimp, in a pot, heat the cooking oil over high heat to 325°F (163°C). Carefully add the shrimp and parsley, then fry for about 3 minutes until light golden and crisp. The shrimp will float, and the bubbling will slow down when ready. Remove and drain on a paper towel-lined plate.
To season and serve, in a bowl, mix together the five-spice powder, white pepper, and salt. Toss the hot shrimp with the seasoning or serve it on the side.