Remove rice from bags. Season chicken with salt and black pepper. Add rice, chicken, broth and buffalo sauce to inner pot of Instant Pot. Close and lock the lid. Select Pressure Cook setting on High Pressure for 5 mins. When pressure cooking is complete, Quick Release the pressure. Once pressure is released, remove lid.
Remove chicken from Instant Pot; shred and return to Instant Pot. Stir in cream cheese and ranch dressing until cream cheese is melted; stir in half of the green onions.
Garnish with remaining green onions.
Sprinkle with crumbled blue cheese if desired.