Put water and frozen edamame in the Instant Pot. Close the lid and turn the valve in a Sealing position. Press the "Pressure Cook" or "Manual" button and set the time to ZERO (0) minutes (edamame will cook just enough while the Instant Pot is coming to pressure).
When it's done cooking, quick release (QR) the steam. Open the lid of the Instant Pot, drain the edamame and sprinkle with salt and pepper to taste.
If you have fresh edamame (not frozen), cook it using the same instructions as frozen.