In a large skillet, heat the olive oil over medium heat. Add the diced chicken and season with garlic powder, onion powder, smoked paprika, salt, and pepper. Cook for about 5-7 minutes, or until the chicken is cooked through and no longer pink in the center.
Add the sliced onion and green bell pepper to the skillet with the chicken. Sauté for an additional 5 minutes, or until the vegetables are tender.
Pour the buffalo sauce over the chicken and vegetable mixture. Stir to combine and let it simmer for 2-3 minutes to heat through.
Preheat your oven to 350°F. Slice the hoagie rolls open and place them on a baking sheet.
Spoon the buffalo chicken mixture evenly into each hoagie roll. Top each with two slices of provolone cheese.
Bake in the preheated oven for about 5-7 minutes, or until the cheese is melted and bubbly.
Remove from the oven and garnish with chopped parsley before serving.