Visa Transparency Anti-Trafficking Act of 2021 This bill directs the Department of Homeland Security to build a searchable database with certain information about each temporary foreign nonimmigrant worker. The database shall include information such as (1) each worker's age, sex, and country of origin; (2) the type of visa used and the status of such visa; (3) where each worker is employed; and (4) each worker's occupation and the compensation received. The database shall only be available to (1) law enforcement, (2) service providers to human trafficking victims, (3) worker protection organizations, and (4) entities agreeing to use the information only for research purposes. The bill expands existing reporting requirements related to temporary foreign nonimmigrant workers to include additional information such as (1) the 10 employers that hired the most temporary foreign nonimmigrant workers, and (2) the 10 occupations with the most temporary foreign nonimmigrant workers.