Marcin Kijak

After installation you can find “Noindex by path” option in the main menu. This allows you to simply add relative paths 
you need to exclude from SERPs. Add a path (including slashes from begging and the end of the string) and save the 
changes. Since this plugin is called to be “simple” you can add only one path at once, but the process is smooth 
and easy.
Plugin will add “noindex” meta tag which is an instruction for search engines that this particular page should not be indexed. 
Technically it modifies wp_head tag.

Noindex by Path

Ask search engines not to index individual pages by a relative path - which means you can set every url no matter it is a page, category listing or an …

amodoke

This plugin lets you Noindex Nofollow All Posts in a category. 
Simply go to Posts > Categories, and click on any category’s EDIT link. 
There you can just “tick” the relevant option you need. 
The plugin will then add a “noindex” or/and “nofollow” line in all posts in that category.
A few notes about the sections above:
<ul>
<li>DigitalChef.in – Madhu Ramrakhyani</li>
<li>This plugin lets you Noindex Nofollow All Posts in a category.</li>
<li>“3.0” is the lowest version that the plugin will work on</li>
<li>“4.7” is the highest version that you’ve successfully used to test the plugin. Note that it might work on 
higher versions… this is just the highest one you’ve verified.</li>
</ul>

NoIndex NoFollow  All Posts

This plugin lets you Noindex Nofollow All Posts in a category.

Noindex by Path vs NoIndex NoFollow All Posts