Add 16×16 favicon after all the links in your posts. 
The favicon’s tag has a ‘favlink’ class so you can CSS it as you wish.

Karedas Favicons

Adds corresponding favicon from Google Shared Stuff after every links in your posts.

HeroThemes

Richard Long

Chris Hadley

“The best Favicon plugin” ★★★★★ – WordPress.org user review.
Simplified and powerful favicons for WordPress.
Add favicons in a flash with Heroic Favicon Generator. This plugin automatically generates favicons using images you upload or select from the media gallery. Support is provided for all modern favicons and automatic generation of the cross-compatible .ico with multiple embedded sizes. Supports different icons for various devices.
Be sure to check the installation and FAQ section to get started and if you have any issues.
<blockquote>
About HeroThemes 
 <a href="https://herothemes.com/" rel="nofollow ugc">HeroThemes</a> develop some of the best WordPress plugins, tools and themes, with over 26,000 customers and counting. If you like this plugin and want more news, themes and plugins, you can do the following:
<ul>
<li>Get the <a href="https://herothemes.com/themes/knowall-wordpress-knowledge-base/?utm_source=wprepo&utm_medium=link&utm_campaign=heroic-favicon" rel="nofollow ugc">KnowAll Knowledge Base theme for WordPress</a>, create a WordPress powered knowledge base site in minutes.</li>
<li>Check out the <a href="https://herothemes.com/plugins/heroic-wordpress-knowledge-base/?utm_source=wprepo&utm_medium=link&utm_campaign=heroic-favicon" rel="nofollow ugc">best WordPress Knowledge Base plugin</a>.</li>
<li>Answer Frequently Asked Questions with <a href="https://herothemes.com/plugins/wordpress-faq-plugin/?utm_source=wprepo&utm_medium=link&utm_campaign=heroic-favicon" rel="nofollow ugc">Heroic FAQs plugin for WordPress</a>.</li>
<li>Follow HeroThemes on <a href="https://twitter.com/herothemes" rel="nofollow ugc">Twitter</a> & <a href="https://www.facebook.com/herothemes" rel="nofollow ugc">Facebook</a>.</li>
</ul>
</blockquote>

Heroic Favicon Generator

Heroic Favicon Generator is your one-click favicon generator for WordPress.

Karedas Favicons vs Heroic Favicon Generator