Season chicken on both sides with salt, pepper, onion powder, and garlic powder. Turn the Instant Pot on the Saute function. Add in butter and minced garlic and saute until fragrant.
Switch to the Pressure Cook function. Add in half of the salsa. Then, add the chicken. Pour the other half of the salsa over the chicken, and sprinkle in the taco seasoning.
Pressure cook on HIGH for 10 minutes. Remove chicken from the Instant Pot, and shred it. Add the shredded chicken back to the pot with the salsa. Toss to ensure that it's evenly coated with sauce.