Mix 2 tablespoons olive oil, rosemary, salt, garlic powder, and sage in a small bowl. Rub all over tenderloins.
Place tenderloins in a medium mixing bowl. Pour lemon and orange juice over the turkey. Cover and marinate in the fridge for 30 minutes. (see note) For a stronger citrus flavor, marinate longer. Reserve the marinade for later one the turkey is ready to cook.
Place 2 tablespoons olive oil in your Instant Pot. Using the saute setting, brown each side of the turkey tenderloin for 2-3 minutes. (For a deeper brown color use 1 Tbsp oil.)
Remove turkey from Instant Pot and set aside on a plate. Add chicken stock and leftover marinade to the Instant Pot.
Place the trivet accessory into the Instant Pot and put the turkey on top. Cover and lock in the lid in place. Set the vent to sealing.
Cook on manual setting (high pressure) for 15 minutes. Let naturally release for 10 minutes, then you can quick release any remaining pressure.
Remove turkey and cut into slices. Serve warm. Store leftovers in an air-tight container in the fridge for up to 3 days.
I have skipped the 30 minutes of marinating time and the flavor, tenderness, and moistness or the turkey was still fabulous. You can skip this step if you need to get dinner on the table ASAP.
If you want to make a gravy to go with this turkey, reserve 1 1/2 cups of the cooking liquid after the turkey is done.