Bring a large saucepan of water to a boil. Add edamame and cook until tender, 4 to 5 minutes or according to package directions. Drain.
Heat oil in a large saucepan over medium heat. Add onion and cook, covered, stirring occasionally, until starting to soften, about 3 minutes. Add zucchini and cook, covered, until the onions are starting to brown, about 3 minutes more. Add garlic, cumin, coriander and cayenne and cook, stirring, until fragrant, about 30 seconds. Stir in tomatoes and bring to a boil; reduce heat to a simmer and cook until slightly reduced, about 5 minutes.
Stir in the edamame and cook until heated through, about 2 minutes more. Remove from the heat and stir in cilantro (or mint) and lemon juice.