Prepare the Bread — Preheat oven to 400°F. Arrange the baguette slices on a lined baking sheet.
Season the Shrimp — Toss the shrimp with melted butter, garlic, paprika, garlic powder, salt, and black pepper.
Mix the Cheese Spread — In a bowl, mix mozzarella, Parmesan, mayonnaise, sour cream, parsley, and half of the green onions until creamy.
Build the Toast Bites — Spread a spoonful of the cheese mixture onto each baguette slice. Place one shrimp on top of each piece.
Bake Until Golden — Bake for 10 to 12 minutes, until the bread is crisp, the cheese is melted, and the shrimp are pink and cooked through.
Finish and Serve — Sprinkle with the remaining green onions and serve warm with lemon wedges.