1. Season turkey with ½ tsp each pepper and salt. Press Sauté on Instant Pot and set to More/High; heat 1 tbsp oil, then swirl to coat bottom of pot. Add turkey breast, skin side down. Cook without moving until skin is golden brown, 1 minute. Transfer to a plate; set aside.
2. Heat remaining 1 tbsp oil. Add onion, celery, carrot, fennel and remaining ½ tsp pepper and ¼ tsp salt; cook, stirring frequently, until onion is tender, 5 minutes. Press Cancel.
3. To a large bowl, add cooked vegetables, bread, pecans, cranberries, 2 tbsp parsley, poultry seasoning and ½ cup broth; stir to combine. Pour stuffing mixture into a 7-inch round metal dish (about 3 inches tall). Cover tightly with foil; set aside.
4. To Instant Pot, add remaining 1½ cups broth, scraping up any brown bits from bottom of pot. Place a trivet (with 2-inch legs) into pot. Place turkey breast, skin side up, on trivet. Place covered stuffing dish onto turkey so it rests on top. Lock lid and set release valve to Seal. Press Pressure and set to More/High; adjust cooking time to 30 minutes.
5. Let pressure naturally release for 10 minutes (don’t move the vent), then carefully set release valve to Venting. When metal pin in lid falls and all pressure is released, unlock lid. Meanwhile, position oven rack 4 inches below broiler and preheat broiler to high. With sturdy tongs or heat-resistant gloves, remove stuffing from pot; discard foil and set aside. Using an instant-read thermometer, check that the thickest part of the turkey reads 165°F. (NOTE: If meat is not done, return turkey to trivet, loosely cover with lid, press Sauté and set to Less/Low; simmer until turkey reaches 165°F.) Transfer turkey to cutting board, cover loosely with foil and let rest 10 minutes.
6. Place stuffing under broiler; broil until golden and crisp on top, 4 minutes.
7. To a small bowl, add flour; gradually whisk in ¼ cup water until mixture is smooth. On the Instant Pot, press Sauté and set to Normal/Medium. Pour flour mixture into pot and whisk into cooking liquid; simmer until gravy is thick and bubbly, 3 to 4 minutes. Add remaining 1 tbsp parsley. Slice turkey and serve with warm stuffing and gravy.