Sparanoid

Displays a user badge next to the comment author name based on author’s role.
<ul>
<li>No database writes, no configurations, install, activate and go.</li>
<li>Easy styles customization via Jetpack Custom CSS or built-in Custom CSS (WordPress version 4.7 or higher required).</li>
<li>Works with <a href="https://wordpress.org/plugins/current-theme-body-class/" rel="ugc">Current Theme Body Class</a> plugin.</li>
</ul>

Comment Author Role Badge

Displays a user badge next to the comment author name based on author's role.

Techspawn

BuddyBadges turns your WordPress site into an achievement & badge system. According to ‘Post’ & ‘Comment’ your users can earn digital badges. Admin can easily defined the badges according to points. BuddyBadges is extremely powerful and infinitely extensible.Given are some of the features of ‘BuddyBadges’ plugin.
Many ways to define achievements and give badges
<ol>
<li>You can give badges to only posts.</li>
<li>You can give badges to only comments.</li>
<li>You can give badges to posts and comments.</li>
</ol>
Buddybadge guide
1) To display all the default badges :- a. To display all badges on use a [displayAllBadgeUser] short-code. 
 b. Related to post the user and badges is display. c. This code is apply only for post.
2) To display all the badges related to post and comment a. To display all badges on use a [displayPostCommentBadge] short-code. 
 b. This is apply only for post and comment.
3) To display badges related to post a.To show only post related badges use a short-code [displayAllBadgeUser bbtype=’post’]. 
 b.This code display all the user regarding to post count. c.if any user can insert most of post related to other user then that user give a badge.
4) To display particular user badges related to post 
 a.To show only particular user related post badges use a short-code [displayAllBadgeUser bbuserid=’User name’ bbtype=’post’]. 
 b.If you display only a particular user badge just insert a name on badge and get a result.
5) To display badges related to comment a.To show only comment related badges use a short-code [displayAllBadgeUser bbtype=’comment’]. 
 b.This code display all the user regarding to comment.
6) To display particular user badges related to comment a.To show only particular user related comment badges use a short-code [displayAllBadgeUser bbuserid=’User name’ bbtype=’comment’]. 
 b.This code display only particular user related comment badge.
7) To display badges related to post and comment a.To show both post and comment related badges use a short-code [displayPostCommentBadge bbcommentlimit=’1′]. 
 b.This code display all the user regarding to post and comment.
8) To display badges related to post and comment a.To show only particular user related post and comment badges use a short-code [displayPostCommentBadge bbuserid=’user name’ bbcommentlimit=’1′]. 
 b.This code display only particular user related post and comment badge. 
 c.Here ‘bbcommentlimit’ is used for dividing total comment count to bbcommentlimit and round number is used for deciding for position for count. if you increate a ‘bbcommentlimit’ then the comment count decrease

buddybadges

Buddybadges turn your side into achievement and badging system. Easily create badges according to its given point.

Comment Author Role Badge vs buddybadges