Sauté carrots, celery, leeks, and onions in butter in a large pan for a few minutes.
Add herbs and seeds, stir in wine and vinegar, then simmer for 30 minutes with water.
Strain the court bouillon into a clean pan and keep it at a gentle simmer.
Season turbot portions and poach in the court bouillon for 4 minutes before removing with a slotted spoon.
Open oysters, reserve their juices, and poach the oysters in the juice for one minute.
Stir soy sauce, butter, shallots, and chives into the oysters and heat for 3 minutes.
Whisk olive oil, vinegar, and shallots together to create a vinaigrette.
Toss the seaweed in the vinaigrette until thoroughly coated.
Serve the poached turbot on warm plates with seaweed salad and oysters on top.