techphernalia

This plugin helps your SEO by adding meta keywords tag to each page, post, archive (category, tag, date, day and year). 
Now it also allows you to specify common keywords to be included on every web page. Plugin from one of the best coder <a href="https://www.techphernalia.com/" rel="nofollow ugc">Durgesh Chaudhary</a>. 
For any support just leave your question at our <a href="https://www.techphernalia.com/meta-keywords-generator/" rel="nofollow ugc">Meta Keywords Generator</a> page.
Uses Title, Description, Categories, tags, Compulsary keywords (provided by you in setting) for keywords generation. Uses content after striping short codes and short tags for generation of description.
Reduces manual work of adding them manually.
Now more efficient by allowing you to add one time master keyword list.
A big Thanks to Omer Barlas for suggesting to change text box to textarea for better readability.

Meta Keywords Generator

Adds Meta keywords and Description to each and every page, post, archive.

gguo01

ADR Promotion Recommendations is a simple plugin that displays promotion recommendations based on page content. Highly relevant promotions are displayed automatically right below your post content. You can also drop it to your sidebar as a widget.
To display promotions, you need to register your site and email contact. Please go to https://www.adrelevantis.com/wp/plugin-register.php for details.

ADR Promotion Recommendations

This plugin displays relevant promotion recommendations below post content and allows you add them in sidebar as a widget.

Meta Keywords Generator vs ADR Promotion Recommendations