Heat oil in the pot of an electric pressure cooker (such as Instant Pot(R)) set on the Saute function.
Season pork chops with black pepper. Cook 2 to 3 chops in the hot oil, flipping halfway, until browned, 7 to 8 minutes. Move to a plate; sear the remaining chops and place on a plate.
Add garlic to the pot and cook until just fragrant, about 30 seconds. Deglaze the bottom of the pot with wine, scraping up any browned bits. Simmer until sauce is reduced by half, 5 to 7 minutes.
Stir mushroom soup and 1 1/4 cup water into the pot with the sauce. Simmer until smooth, about 3 minutes. Add the seared pork chops and turn to coat. Close and lock the lid. Select high pressure according to manufacturer's instructions; set timer for 18 minutes. Allow 10 to 15 minutes for pressure to build.
Release pressure using the natural-release method according to manufacturer's instructions, about 10 minutes. Remove chops from the pot.
Mix 1/4 cup water and flour together; add slurry to the pot. Select Saute function and cook until gravy is thickened, about 3 minutes. Add soy sauce and stir well. Return chops to the pot and turn to coat.