Combine ground turkey, breadcrumbs, Parmesan cheese, egg, Italian seasoning, salt, black pepper, and chopped parsley in a large mixing bowl. Mix gently until just combined. Form mixture into 1-inch meatballs.

Turn on the Instant Pot and select the "Sauté" function. Once hot, add olive oil and let heat for about 2 minutes. Carefully place meatballs in the pot and brown them for about 5 minutes.

In the same pot, add flour and stir continuously for about 1 minute to create a roux. Gradually pour in the broth, whisking constantly. Mix in Worcestershire sauce and let simmer for 2-3 minutes to thicken.

Return browned meatballs to the pot, coat with gravy, secure lid, and set the valve to sealing. Select "Manual" or "Pressure Cook" and set timer for 5 minutes.

After cooking, perform a quick release of the pressure. Remove meatballs and stir heavy cream into the remaining gravy, letting it simmer for an additional 2-3 minutes.

Garnish the dish with extra parsley and serve meatballs drizzled with gravy alongside mashed potatoes, rice, or vegetables.