Select SAUTÉ setting on a programmable pressure multicooker (such as Instant Pot). (Times, instructions, and settings may vary according to cooker brand or model.) Select HIGH temperature setting, and allow to preheat 2 to 3 minutes. Melt 1 tablespoon of the butter in cooker. Sprinkle pork with salt and pepper; add pork to cooker, and cook until browned on 1 side, about 5 minutes. Remove pork from cooker. Add garlic to cooker; sprinkle with flour, and stir. Stir in stock, orange juice, lemon juice, and honey. Return pork to cooker. Press CANCEL.

Cover cooker with lid, and lock in place. Turn steam release handle to SEALING position. Select MANUAL/PRESSURE COOK setting. Select HIGH pressure for 3 minutes. (It will take 10 to 15 minutes for cooker to come up to pressure before cooking begins.)

Carefully turn steam release handle to VENTING position, and let steam fully escape (float valve will drop). (This will take 2 to 3 minutes.) Remove lid from cooker. Transfer pork to a serving platter. Add remaining 3 tablespoons butter to cooker; stir to melt. Stir in parsley. Slice pork, and drizzle with sauce.