The Accounts tab has two subtabs:
Server Access Management
Server Access Management enables you to list existing user accounts. You can also add and delete accounts. You can allocate administrative roles and also set account limits.
Schema Privileges enables you to set specific privileges on a user basis.
In the current version of MySQL Workbench, it is not possible to manage privileges below the schema level. For example, it is not possible to view or manage grants at the table, column, or procedure level.