Edamame is the immature soy bean, which is a legume.
“Edamame and all preparations of soybeans are rich in carbohydrates, protein, dietary fiber, and micronutrients, particularly folates, manganese, and vitamin K” Source
“A ½-cup serving of shelled edamame contains only 100 calories, with 3 g of unsaturated fat and 8 g of protein. It also provides 4 g of fiber and is a good source of calcium, copper, folate, iron, magnesium, manganese, phosphorus, thiamin, vitamin A, vitamin C and vitamin K. Edamame doesn’t contain any cholesterol and has very little sodium.”