Persimmons and crabs really can't be eaten together. They will react with each other, causing vomiting, abdominal pain, and even stomach persimmon stones. But it is too exaggerated to say that eating together will be poisoned.
Because crab meat tastes delicious, it contains high protein, fat, calcium, phosphorus, etc. Persimmon is rich in sugar, pectin, minerals and vitamins, and also contains more tannic acid.
These two foods do not contain any toxins in themselves, except that they contain slightly different nutrients.