Peel and chop the onions. Heat the oil in a large pan. Brown the onions in it. Add the rice and fry until transparent. Season with salt, pepper and saffron. Add stock and let everything swell for about 40 minutes at low heat in the closed pan.
Wash the lemons thoroughly and cut them into slices. Add the crab meat, peas and lemon slices, except for a few for garnishing, to the rice 10 minutes before the end of the cooking time. Wash the dill, dab dry and cut finely except for one bunch for garnishing.
Fold half into the rice. Season the risotto to taste again. Sprinkle with remaining dill and serve garnished with lemon wedges and a bouquet of dill.