Trim any visible fat from the chicken breasts and cut each breast into 3–4 lengthwise strips.
Place the chicken strips in the Instant Pot. Add 1/2 cup Pace Picante Sauce, 1 tsp onion powder, and 1 tsp garlic powder; stir gently to coat.
Close and lock the Instant Pot lid and set the valve to SEALING. Cook on HIGH PRESSURE for 8 minutes.
When the cook time ends, allow a 10-minute NATURAL RELEASE, then move the valve to VENTING to quick-release any remaining pressure. Open the lid.
Use tongs to transfer the chicken strips to a cutting board and let them rest briefly so they’re easier to handle.
While the chicken rests, set the Instant Pot to SAUTÉ on LOW. Let the cooking liquid in the pot simmer until it reduces to about 1/2 cup (about 3–6 minutes).
Meanwhile shred the chicken with two forks into bite-size pieces.
Turn the Instant Pot off. Add 1 T Green Tabasco Sauce, 2 T fresh-squeezed lime juice, the entire can (4 oz) diced green chiles with their juice, and the 4 oz cream cheese (in cubes) to the reduced liquid. Whisk or stir until the cream cheese is melted and the sauce is smooth and creamy.
Return the shredded chicken to the Instant Pot and stir to combine. If the chicken has cooled, turn SAUTÉ/LOW on for 1–2 minutes to warm through.
Add 3/4 cup grated Mexican Blend cheese to the chicken mixture and stir until the cheese is melted and evenly incorporated. Turn the Instant Pot off.
Heat the tortillas in a hot, dry skillet about 1 minute total (flip once) until warmed and pliable.
Fill each tortilla with the creamy chicken mixture, then sprinkle with the remaining about 3/4 cup grated Mexican Blend cheese reserved for serving. Top with sliced olives and/or sliced green onions if desired. Serve immediately.