In a large bowl, add shrimp to the whisked egg white and stir. Add cornstarch and toss to coat.
In a small bowl or measuring cup, whisk together the apple cider vinegar, pineapple juice, ketchup, soy sauce, honey, garlic, and ginger. Set aside until ready to use.
In a small bowl, combine water and cornstarch. Set aside until ready to use.
Heat oil in a wok or large pan over medium-high heat. Add the shrimp in a single layer and fry for 1 minute. Turn the shrimp to other side and cook another 30 seconds. Transfer to a cooling rack. Discard all but 2 tablespoons of oil.
In the same pan, heat the reserved oil. Add the bell peppers, zucchini, and pineapple, cook for 2 minutes, or until soft and golden around the edges. Pour the sweet and sour sauce in the pan and the cornstarch mixture and stir constantly until the sauce is thickened, about 30 seconds.
Add the fried shrimp, stir to combine and cook until shrimp are warmed through, 1 to 2 minutes.
Garnish with green onions and sesame seeds. Enjoy!