In a food processor, pulse scallops and egg just until scallops are chopped. With motor running, pour in cream and whirl until smooth.
Scrape scallop mixture into a bowl. Stir in crab, bell peppers, cilantro, 2 tbsp. chives, the hot sauce, salt, and cayenne, breaking up most large chunks of crab.
Lay an 18-in. sheet of parchment paper on a work surface. Scoop 6 equal mounds of crab mixture onto parchment. Shape each into an even cake about 1 1/4 in. thick, using your fingers or, for neater sides, a 2 1/2-in.-diameter ring mold.
Pour olive oil into a 12-in. nonstick frying pan and heat over medium-low heat. Using a thin, flexible spatula, carefully transfer cakes to pan. Cook, turning once, until nicely browned and no longer wet in center, about 10 minutes total. Divide crabcakes among 6 warm plates, scatter with remaining 1 tbsp. chives, and serve with Devil Sauce.
Note: Nutritional analysis is per serving, without sauce.