Kuuak

Simply force display and move the excerpt input box right below the title and before the content.

Excerpt below Title

Move the excerpt metabox below the post title

WPKube

FancyThemes

This plugin adds several improvements to WordPress’ default way of creating excerpts.
<ol>
<li>Keeps HTML markup in the excerpt (and you get to choose which tags are included)</li>
<li>Trims the excerpt to a given length using either character count or word count</li>
<li>Only the ‘real’ text is counted (HTML is ignored but kept)</li>
<li>Customizes the excerpt length and the ellipsis character that are used</li>
<li>Completes the last word or sentence in an excerpt (no weird cuts)</li>
<li>Adds a read-more link to the text</li>
<li>Ignores custom excerpts and use the generated one instead</li>
<li>Theme developers can use <code>the_advanced_excerpt()</code> for even more control (see the FAQ)</li>
</ol>
Most of the above features are optional and/or can be customized by the user or theme developer.
Banner image credit – <a href="https://www.flickr.com/photos/chillihead/" rel="nofollow ugc">chillihead</a>
Original plugin author – <a href="https://profiles.wordpress.org/basvd" rel="nofollow ugc">basvd</a>
Useful Resources
<ul>
<li><a href="https://fancythemes.com/what-is-wordpress/" rel="friend nofollow ugc">What is WordPress</a></li>
<li><a href="https://fancythemes.com/wordpress-themes" rel="friend nofollow ugc">Fee Themes</a> and <a href="https://fancythemes.com/wordpress-plugins/" rel="friend nofollow ugc">plugins</a></li>
</ul>

Advanced Excerpt

Control the appearance of WordPress post excerpts

Excerpt below Title vs Advanced Excerpt