Wordpress plugin to display categories on sidebar with more customization options from the backend https://wordpress.org/plugins/display-categories-widget/
Display Categories Widget will display Child categories on your sidebar. Can be placed on widget in sidebar.
Features:
- Limit number of categories that appears.
- Exclude categories from display.
- Restrict levels of categories that can be shown.
- Display categories as list or dropdown.
- Hide categories that does not have any posts.
- Display/Hide number of posts available in categories.