The Yoast SEO Premium plugin (formerly known as WordPress SEO by Yoast Premium) adds several features to the Yoast SEO plugin. At the moment, the extra included functionality includes:
A redirect manager
This allows you to create and manage redirects from within your WordPress install, allowing you to easily redirect old URLs to new ones, and solve common issues. This is especially powerful because of the combination with the Google Webmaster Tools integration.
Built for scale, this redirect module can either handle the redirects for you or generate a redirect file that you can include in your Apache or NGINX server config.
Multiple focus keywords
With this feature, you’ll be able to optimize a post for two completely different terms, or for two synonyms. This means you no longer have to choose between terms you’d like to rank for!