Heat the oven to 400°F. Roast the poblano until the skin is blistered and the flesh is soft, about 30 minutes. Cool, peel and seed the chile.
Combine the tomatoes, carrots, cucumbers, onions, garlic, fresno, poblano, lime juice, sherry vinegar, tomato juice, bread, salt and ⅓ cup cilantro in a food processor and purée until smooth. Chill the soup in the refrigerator for at least 30 minutes.
Place 2 ounces of crab into each of 6 bowls and evenly distribute the soup on top. Garnish with the remaining cilantro and olive oil (plus tomato and cucumber, if using) to serve.