Combine the coconut milk, water, blueberries, chia seeds, oats, maple syrup, and vanilla extract in the inner pot.
Lock the lid into place. Select Pressure Cook or Manual; set the pressure to High and the time to 3 minutes. After cooking, naturally release the pressure for 5 minutes, then quick release any remaining pressure.
Unlock and remove the lid. Pour the pudding into individual serving cups and refrigerate until it sets, about 1 hour.
Serve cold garnished with berries, or cover tightly and refrigerate for up to 4 days.