Warm 1 1/2 tsp. oil in a large skillet over medium-high heat. Cook sausages, stirring, until browned, 4 to 5 minutes. Transfer to a plate.
Warm remaining oil in skillet. Add apples, sprinkle with sugar and cook, turning occasionally, until light golden and slightly tender, about 5 minutes. Transfer to a plate.
Return sausages to skillet. Add wine and vinegar. Bring to a boil. Reduce heat and simmer until liquid has thickened, about 5 minutes. Return apples to skillet to reheat. Stir in thyme; season with salt and pepper. Serve immediately.