In a large, heavy-bottomed pot or Dutch oven, combine the wings, soy sauce, sugar, garlic, ginger, five-spice, Szechuan peppercorns, dried chiles, scallion greens (reserve the sliced whites for garnish) and star anise. Mix all of the ingredients until well combined. You may marinate the wings overnight for a deeper flavor, if you wish.
Add the rice vinegar and beer to the pot. Bring the pot up to a boil over high heat, and then lower the heat to a rolling simmer. Braise the wings, uncovered, until they are tender, about 1 hour. Remove the wings from the braise to a sheet tray and refrigerate until cold.
Reduce the braise over medium heat until the consistency can thinly coat the back of a spoon. Strain the braising liquid through a fine mesh sieve, discarding the solids. Whisk in the butter to the glaze. Check for seasoning.
Preheat the deep-frying oil in a large pot to 375 degrees F.
Pat the chilled chicken wings dry, and then toss to coat in the cornstarch-flour mixture, shaking off any excess flour.
Deep-fry the wings in small batches, being careful to not overcrowd the pot, until dark brown and crispy, about 3 minutes. Drain the wings from the oil into a large bowl, adding the spicy beer glaze and tossing until well coated. Serve the wings hot garnished with the sliced scallion whites.