Mix grated vegetables and squeeze out liquid using kitchen paper.
Combine soy, ponzu, vinegar, and grapeseed oil with vegetables and season with pepper.
Mix myoga, ginger, and shiso, then chill in iced water.
Preheat a deep-fat fryer to 180°C.
Wash julienned potatoes in ice cold water and drain well.
Toss potatoes with potato starch until individual pieces are coated.
Deep-fry potato strips until golden-brown, season with salt, and drain on kitchen paper.
Drain salad, arrange on plates, and top with sea bream slices.
Drizzle dressing over the dish and serve with fried potatoes.