Preheat the oven to 375°F (190°C).
Bring a large pot of salted water to a boil. Add the bell peppers and cook for 3-4 minutes until slightly softened. Remove and drain upside down on paper towels.
In a large skillet, melt the butter over medium heat. Add the minced garlic and cook for 1 minute until fragrant.
Add the shrimp to the skillet and season with salt, black pepper, and smoked paprika. Cook for 2-3 minutes on each side until shrimp turn pink and are cooked through. Remove from heat.
In a medium bowl, combine the cooked shrimp (chopped into bite-sized pieces if desired), cooked rice, mozzarella cheese, Parmesan cheese, and chopped parsley. Mix well.
Stuff each bell pepper with the shrimp and rice mixture, pressing down gently to fill completely.
Place the stuffed peppers upright in a baking dish. Cover loosely with foil.
Bake in the preheated oven for 15 minutes. Remove the foil and bake for an additional 5-7 minutes until the cheese is melted and the peppers are tender.
Remove from oven and let cool for 5 minutes before serving.