Preheat the oven to 325 degrees F (165 degrees C).
Combine paprika, garlic powder, black pepper, sea salt, and cayenne pepper in a bowl; set aside.
Heat olive oil in a large skillet over medium heat. Add mushrooms and shallots; cook and stir until mushrooms release their liquid, 5 to 8 minutes. Set aside.
Melt ¼ cup margarine in a large skillet over medium-high heat; stir in ¼ cup Worcestershire sauce. Thoroughly rub beef brisket with spice mixture; place brisket in skillet.
Brown brisket on all sides, about 5 minutes per side. Add 1 ½ cups Worcestershire sauce to the skillet, ½ cup at a time, adding more as sauce cooks into brisket.
Place a rack in a heavy Dutch oven; place brisket on the rack. Pour in Worcestershire sauce skillet drippings, beef broth, red wine, water, and garlic; top with mushroom mixture. Drizzle remaining 1 tablespoon Worcestershire sauce over mushrooms; top with remaining 2 tablespoons margarine. Cover the Dutch oven.
Bake in the preheated oven for 3 hours. Reduce the oven temperature to 300 degrees F (150 degrees C); bake for 1 hour more. Reduce the oven temperature to 225 degrees F (105 degrees C); bake for 1 hour more. Baste with pan drippings every hour.
Rest brisket before slicing thinly against the grain, about 20 minutes. Serve with pan gravy.