Preheat oven to 350 degrees F. In a medium skillet over medium heat, melt olive oil. Add onion and bell pepper and cook until onion is translucent, about 5 minutes. Season with a pinch of salt.
Push onions and peppers to the side and add shrimp and minced garlic to the skillet. Cook until shrimp is pink and garlic is fragrant; 1-2 minutes. Mix with the onions and peppers during the last 30 seconds.
Stir in cajun seasoning, lemon juice, and Worcestershire sauce and heat to a simmer.
Remove pan from heat and stir in cream cheese, 1/2 cup of mozzarella cheese, Parmesan, and green onions.
Stir until all cheese is melted and all ingredients are evenly distributed. Sprinkle with remaining cheese.
Bake in the preheated oven for 15-20 minutes or until golden and bubbly. If you want a more golden top, add a few minutes under the broiler.
Garnish with remaining green onions and serve with crackers or toasted bread.