Pull sausages into chunks and put in a 10- to 12-inch frying pan over medium-high heat. Add onion and garlic; cook, stirring often to crumble meat, until sausage is browned, 7 to 10 minutes. Add broth and soybeans and bring to a boil; reduce heat to low and simmer, uncovered, stirring occasionally, until beans are hot, 3 to 5 minutes.
Meanwhile, in a 5- to 6-quart pan over high heat, bring about 3 quarts water to a boil. Add linguine and stir occasionally until barely tender to bite, 7 to 9 minutes. Drain pasta and return to pan.
Add sausage-soybean mixture to linguine and stir over medium heat until hot. Mix in parsley, parmesan cheese, and salt and pepper to taste. Pour into a serving bowl.