Place potatoes, sausage, onion, 3 teaspoons Old Bay seasoning and hot sauce into a 6-qt Instant Pot®. Stir until well combined. Top with corn and beer.
Select manual setting; adjust pressure to high, and set time for 5 minutes. When finished cooking, quick-release pressure according to manufacturer’s directions.
Add shrimp. Select manual setting; adjust pressure to high, and set time for 1 minute. When finished cooking, quick-release pressure according to manufacturer’s directions.
Melt butter in a small skillet over medium low heat. Stir in garlic and remaining 1 teaspoon Old Bay seasoning until fragrant, about 1-2 minutes.
Serve shrimp mixture immediately, drizzled with butter mixture, garnished with parsley and lemon, if desired.