In a bowl, season the peeled and deveined shrimp with a pinch of salt and a pinch of white pepper. Set aside.
In a small separate bowl, combine 2 tablespoons soy sauce, 1 tablespoon oyster sauce, and a pinch of white pepper. Mix well to create the stir-fry sauce.
Heat a wok or large skillet over high heat. Add 1 tablespoon of oil. Add the shrimp and sear for 1-2 minutes until pink and just cooked through. Remove shrimp from the pan and set aside.
Add another 1 tablespoon of oil to the pan. Pour in the beaten eggs and quickly scramble them until set. Remove eggs from the pan and set aside with the shrimp.
Add the remaining 1 tablespoon of oil to the pan. Add the diced onion, peas, carrots, and corn. Stir-fry for about 1-2 minutes until onions are translucent and veggies are tender.
Add the overnight rice to the pan. Break up any clumps with a spatula and toss with the vegetables.
Pour the prepared sauce mixture over the rice. Stir-fry constantly on high heat, ensuring the rice is evenly coated and heated through.
Add the cooked shrimp, scrambled eggs, and chopped scallions back into the pan. Toss everything together for another minute to combine flavors.
Serve immediately while hot.