Pour 1/2 cup water into the bottom of an Instant Pot
or electric pressure cooker. Place the steamer basket in the pot, then add the squash, cut sides up (they will overlap). Be sure not to exceed the max fill line. If your squash are larger and you exceed the line, cook the squash in two batches. Seal the lid, set pressure valve to sealing, and cook on HIGH (manual) for 4 minutes. Allow the pressure to release naturally for 5 minutes, then immediately vent to release any remaining pressure. Drain and arrange on a large serving plate or baking sheet.