Bring a large pot of water to a boil. Add spaghetti and edamame and cook, stirring occasionally, until the pasta is just tender, 8 to 10 minutes or according to package directions. Drain.
Meanwhile, whisk scallions, oyster sauce, vinegar, soy sauce, sugar, sesame oil and crushed red pepper in a small bowl until the sugar is dissolved.
Heat canola oil in a large nonstick skillet over high heat. Add carrots and bell peppers and cook, stirring often, until slightly softened, 3 to 4 minutes. Add the pasta and edamame. Cook, stirring occasionally, until the pasta is crispy in spots, 1 to 2 minutes. Add the sauce and stir to combine.
