Dimox

Plugin replaces comment author link and (or) links in comment text on jQuery links that will work (i.e. it will be possible to go on the specified site through these links) only in case when the JavaScript technology is enabled in a browser of the visitor of your site.
When can this plugin might be useful:
<ul>
<li>If you want to reduce the number of external links on your site (for example, for any SEO reasons).</li>
<li>If you don’t want to refer to bad sites and you don’t have time and desire to check the links, which are left by the authors of comments.</li>
</ul>
Here is how it looks. For example, there is such a link on the name of comment author:
<pre><code><a href='http://sitename.com' rel='external nofollow' class='url'>Comment Author Name</a>
</code></pre>
After plugin activation this link will turn to the such:
<pre><code><a href="#" class="jqcl" title="sitename.com" rel="nofollow">Comment Author Name</a>
</code></pre>
This is jQuery link, that will work only if JavaScript technology is enabled in a browser of the visitor of your site.
Links to your site will not be replaced.

jQuery Comment Links

Plugin replaces comment author link and (or) links in comment text on jQuery links.

royalnavneet

<ul>
<li>Website Comment Cleaner – Delete All Comments, Disable Comments, Bulk Delete & Remove Comments** helps you delete, export, import, and disable comments on your WordPress site using an admin dashboard with bulk actions and filters.</li>
</ul>
This plugin supports: 
* Deleting comments by status (approved, pending, spam, trash, or all). 
* Optional date-range filtering when bulk deleting. 
* Exporting comments to CSV and importing comments from CSV. 
* Disabling comments globally or by selected post types. 
* Role-based exclusions and scheduled spam cleanup.
<h3>Features</h3>
<ul>
<li>Export comments to CSV from the plugin dashboard.</li>
<li>Import comments from CSV.</li>
<li>Schedule automatic spam cleanup (daily, weekly, monthly).</li>
<li>Configure role-based exclusions and post-type comment settings.</li>
</ul>

Comment Cleaner — Bulk Delete & Disable Comments

Delete, export, import, and manage WordPress comments with bulk tools and comment-control settings.

jQuery Comment Links vs Comment Cleaner — Bulk Delete & Disable Comments