Place lentils and 1 bay leaf in a saucepan with enough water to cover; bring to a boil. Reduce heat to medium-low and simmer until lentils are tender, about 30 minutes; drain and discard bay leaf. Rinse lentils with cold water until cool, then transfer to a large bowl.

Bring 2 cups water, quinoa, and remaining bay leaf to a boil in a saucepan. Reduce heat to medium-low, cover, and simmer until quinoa is tender and water has been absorbed, 15 to 20 minutes. Rinse quinoa with cold water until cool, discarding bay leaf. Stir quinoa into lentils.

Heat lemon juice in a microwave-safe bowl in a microwave until warm, about 30 seconds. Stir honey into juice until dissolved. Add vinegar and salt; whisk in olive oil and season with black pepper. Pour lemon juice mixture into lentils and quinoa.

Mix walnuts, cranberries, feta cheese, and green onion into lentil and quinoa salad. Toss to coat. Refrigerate until chilled, about 1 hour.