Combine oil and flour in a heavy skillet; cook over medium heat for 20 minutes, stirring constantly, until roux is dark. Be very careful to keep the roux from scorching. Stir in onion, celery, and garlic; cook 10 minutes, stirring often.
Transfer mixture to a Dutch oven or large kettle. Add chicken broth, tomatoes, okra, crab claws, Worcestershire sauce, hot sauce, bay leaves, parsley, thyme, basil, oregano, sage, and pepper; simmer 2 hours, stirring occasionally.
Add shrimp, oysters, crab meat, and fish to the pot; simmer 10-15 minutes. Remove and discard bay leaves.
Serve gumbo over hot cooked rice and, if desired, sprinkle with filé or chopped parsley.