Place 1 C water and trivet into the Instant Pot.
Using a fork, poke holes in the potatoes and place on top of the trivet. Close lid and select the manual option adjusting cooking time to 9-10 minutes. After pressure cooking cycle hasended, let instant pot natural release for 10 minutes, then turn the vent to quick release to ventany remaining pressure.
Preheat oven to 350° (F)
Using tongs, and being careful not to remove any skins, place potatoes on a cooling rack. When cool enough to handle, cut potatoes in half lengthwise and spoon out the insides into a large bowl.
Place skins on a large sheet pan.In the potato bowl, add the sour cream, melted butter, cream cheese, green onions, salt, pepper, milk, and seasoning packet. Mash and stir until smooth. Fold in half of the cheese.
Spoon the mixture back into the potato skins. Top with remaining cheese and bake in the oven for 20 minutes.