Codesoftech

Convert your default wordpress comment form into ajax submit.
<h4>Features</h4>
Ajax Comment Form CST allows you to convert your default comment form into ajax submit. 
It will also add GDPR field for comment form that can be removed from setting option. 
File (JS / CSS / PHP) will be added only to the selected pages, which will good for your website PLT (Page load time).
<ul>
<li>Ajax request for Post and Page comment form.</li>
<li>Messages can be cutomised.</li>
<li>Captcha on / off settings. </li>
<li>GDPR field can be enabled that will automically add a field in comment form and new column on comments list on backend.</li>
<li>You can write your own CSS.</li>
</ul>

Ajax Comment Form CST

Easy to use

Wordpress default comment form into ajax submit.

llavillaccama

Ajax functionality to comments, this plugin makes the error message is displayed in a popup window and updates the comments.
<a href="http://webdesignjc.com/recaptchawp/index.html" rel="nofollow ugc">Plugin Website</a>

JC Ajax Comments

Ajax in wordpress comments, this plugin makes the error message is displayed in a popup and updates the comments.

Ajax Comment Form CST vs JC Ajax Comments