Heat a large skillet over medium heat. Crumble the turkey sausage into the pan and cook, stirring frequently, until fully cooked. Remove the cooked sausage with a slotted spoon, drain on a paper towel, and place in a medium mixing bowl, reserving the drippings in the pan.
In the same skillet with the reserved drippings, spread the hash browns in a thin layer. Season with salt and pepper. Cook for about 7 minutes or until the bottom is golden and crispy. Flip and cook the other side until also browned and crispy. Remove from the skillet and add to the bowl with the cooked turkey sausage.
Return the skillet to the heat and melt the butter. Pour in the whisked eggs and scramble until cooked through. Add the scrambled eggs to the bowl with the sausage and potatoes, stirring to combine all ingredients evenly.
In a separate bowl, whisk together the cream of mushroom soup, sour cream, green enchilada sauce, green chilies, and chopped green onions. Set aside 1 cup of this sauce mixture and stir the remaining sauce into the egg mixture.
Preheat the oven to 325°F.
Spread about 1 cup of the egg mixture onto each tortilla and roll them up tightly. Arrange the rolled tortillas seam-side down in a 9×13-inch baking dish. Pour the reserved sauce over the enchiladas and sprinkle evenly with cheddar and pepper jack cheeses.
Bake for 30 to 35 minutes, or until the cheese is melted and the sauce is bubbly. Remove from oven and allow to rest for 5 to 10 minutes before serving. Makes 8 servings.