Heat the soy sauce, vinegar, sugar, and ginger in a large nonstick skillet over medium heat until the sugar melts, about 3 minutes.
Season the chicken with ½ teaspoon salt and ¼ teaspoon pepper and add to the skillet. Cook 3 minutes per side.
Add the onion, pear, wine, and orange zest and juice. Cover, reduce heat to low, and cook until cooked through, 12 to 15 minutes.
Transfer the chicken and pear slices to plates.
Simmer the sauce until thickened, 1 to 2 minutes, and pour over the chicken.