Preheat oven to 375°F (190°C).
Brush bell pepper halves lightly with olive oil and place in a baking dish.
In a mixing bowl, combine shredded chicken, buffalo sauce, and cream cheese.
Stir until the filling is well mixed and creamy.
Spoon the buffalo chicken mixture evenly into each pepper half.
Top stuffed peppers with cheddar and mozzarella cheese.
Cover the baking dish with foil and bake for 20 minutes.
Remove foil and bake for an additional 5 minutes until cheese is melted.
Remove from oven and let rest briefly.
Garnish with chopped green onions before serving.