Place the scallops on a large plate lined with a paper towel and pat dry. Combine the lime juice, shallot, chili sauce, fish sauce and 1/4 cup vegetable oil in a large bowl; whisk to combine. Add the cabbage, cucumbers, radishes, apple and basil to the dressing and toss well to coat.
Heat the remaining 1 tablespoon vegetable oil in a large nonstick skillet over high heat. Add the scallops in an even layer (do not crowd the pan). Cook, undisturbed, until a golden crust forms on the bottom of the scallops, about 3 minutes. Flip the scallops (they should release easily from the pan; if they stick, cook 1 more minute). Cook until lightly browned on the other side, about 2 minutes.
Divide the cabbage salad among plates and add the scallops. Top with the peanuts and serve with lime wedges.