Season the shrimp with 1/2 teaspoon salt in a large bowl. Add the cornstarch and toss to coat; set aside. Juice 3 blood oranges into a small bowl; add the vinegar, honey, ketchup, sesame oil and 1/2 teaspoon salt and whisk to combine. Quarter the remaining 2 oranges and thinly slice; set aside.
Fill a large bowl with ice water and set aside. Bring a medium pot of salted water to a boil. Add the snow peas and cook until crisp-tender, about 1 minute. Drain and immediately transfer to the ice bath; let sit until cool, then drain and pat dry.
Heat a large nonstick skillet or wok over high heat; add 2 tablespoons vegetable oil. Add the shrimp and cook, stirring occasionally, until lightly browned and opaque, 1 to 2 minutes. Transfer to a plate with a slotted spoon.
Add the remaining 1 tablespoon vegetable oil and the chiles to the skillet. Cook, stirring occasionally, until lightly toasted, about 1 minute. Add the garlic and ginger. Cook, stirring, until golden, about 30 seconds. Add the blood orange juice mixture and bring to a simmer. Cook, stirring, until slightly thickened, 2 to 3 minutes.
Return the shrimp to the skillet and stir until warmed through, about 1 minute. Add the snow peas, scallions and blood orange slices; toss to combine. Sprinkle with the sesame seeds and serve with rice.