Preheat the oven to 425 degrees F (220 degrees C). Grease a rimmed baking sheet with cooking spray.
Combine cabbage, apple, onion, olive oil, vinegar, salt, and pepper in a large bowl; toss until well coated. Place in a single layer on the prepared baking sheet.
Bake in the preheated oven until slightly tender, about 20 minutes. Toss cabbage mixture and place sausages on top. Bake until sausages are crispy and cabbage has caramelized, about 10 minutes more.