Julian Widya Perdana

Automatically adds keywords and description meta tag on every page based on title, tags, categories, etc. Simple but powerful !
If the page is post, it will sets all title, category, and tags as keywords meta tag. If it is category page, the keywords will be your category name, same work for tags.
It may reduce your work on typing manual keywords every post or even every page of your blog and it is easy-to-use.

Automated Keywords Generator

Automatically adds keywords and description meta tag on every page based on title, tags, categories, etc. Simple but powerful !

Musilda

Allow you to add custom meta tags and title for category. 
In next version will be added other seo plugins support.

WP Custom Category Meta

Allow you to add custom meta tags and title for category.

Automated Keywords Generator vs WP Custom Category Meta