Preheat oven to 500°F. Melt butter with oil in heavy large ovenproof skillet over medium-high heat. Stir in garlic and green onion. Add crabs. Sprinkle 1 tablespoon chopped thyme and 1 tablespoon chopped parsley over crabs. Stir to combine.
Place crab legs in oven dish and pour melted butter mixture over crab. Roast crabs until heated through, stirring once, about 12 minutes. When Crabs are roasted, pour crab drippings from roasting dish back into the skillet you used before and add orange juice and peel to same skillet; Add the other tbs of Thyme and Parsley. Boil until sauce is reduced by about half and serve drizzled over crab and along side it for dipping.