Season the pork chops on both sides with salt, black pepper, garlic powder, onion powder, and smoked paprika.
Set the Instant Pot to saute mode and add the olive oil and butter. Once the butter is melted and hot, sear the pork chops for 2 to 3 minutes per side until golden brown. Work in batches if needed to avoid crowding. Remove and set aside.
Add the sliced onion to the pot and cook for 3 minutes until softened. Add the garlic and cook for 30 seconds. Pour in the chicken broth, dijon mustard, and worcestershire sauce, stirring to combine and scraping up any browned bits from the bottom.
Return the pork chops to the pot, nestling them into the liquid. Lock the lid and set the valve to sealing. Pressure cook on high for 8 minutes.
Allow a natural pressure release for 5 minutes, then carefully switch the valve to venting. Remove the lid once the pin drops and transfer the pork chops to a plate.
In a small bowl, whisk together the cornstarch and cold water. Set the Instant Pot to saute mode and stir the cornstarch slurry into the sauce. Let it simmer for 2 to 3 minutes until the gravy thickens.
Spoon the gravy and onions over the pork chops, sprinkle with fresh parsley, and serve immediately.