Select the Sauté function on your Instant Pot. Add a drizzle of oil and the pork pieces, then cook for 5 minutes, stirring occasionally, until the pork develops some color.
Add the kimchi, garlic, and sesame oil. Stir and sauté for another 5 minutes.
Pour in the rice water, kimchi juice, and soy sauce, then stir well. Close the lid and set the Instant Pot to Soup mode for 30 minutes.
Once the cooking program is complete, allow the pressure to naturally release.
Switch back to Sauté mode and add the tofu, mushrooms, green onions, sugar, MSG, and pepper. Mix well and sauté for 5 minutes, or until everything is heated through.