Turn on a multi-functional pressure cooker (such as Instant Pot), select Saute function, and let pot heat up. Meanwhile, season pork chops with salt and pepper.

Add oil to hot pot. Brown chops 1 to 2 minutes per side and set aside on a plate. Add onion and garlic to the drippings in the pot and cook until tender, about 3 minutes. Pour in red wine and cook, scraping bits from the bottom of the pot, until most of the alcohol has cooked off, about 5 minutes. Pour in beef consomme. Add rosemary and stir around. Return browned chops to the pot.

Close and lock the lid. Set vent to sealing and select high pressure according to manufacturer's instructions. Set timer for 40 minutes. Allow 10 to 15 minutes for pressure to build.

Release pressure using the natural-release method according to manufacturer's instructions for 15 minutes. Release any remaining pressure carefully using the quick-release method according to manufacturer's instructions, about 5 minutes. Unlock and remove the lid.

Transfer chops to a plate. Choose Saute function on the pot and bring liquid to a boil. Combine cornstarch and water in a bowl to create a slurry and add to the pot. Cook and stir until thickened, about 5 minutes.

Return chops to the pot and stir to coat.