No, FacetWP does not support filtering directly on categories or taxonomy terms, with one exception: product categories on WooCommerce shop- and product category archive pages.

But you can filter posts, pages, and posts of any custom post types by category or taxonomy term(s): by setting a taxonomy as a facet’s data source.

Besides posts, pages and custom post types, you can filter users, if you install the User Post Type add-on, which comes with a Professional license.

See also