CRP Taxonomy Tools is an extension for Contextual Related Posts that adds another degree of related posts matching by adding the option to restrict these related posts to the same category, tag or custom taxonomy. This plugin adds additional checkboxes under General options under the Related Posts page.

Additionally, you can also disable the contextual matching engine either on posts/pages or on only custom post types.

CRP Taxonomy Options

Requires Contextual Related Posts v2.0 or higher.