Prime Strategy

<p>This plugin rewrite “wp-config.php” to enable access multiple domain.<br />
It will be great help to link check of your WordPress site or mirroring for test.</p>
<h4>Functions</h4>
<ul>
<li>Rewrite “wp-config.php” automatilally.</li>
<li>Enable multi domain access on demand.</li>
</ul>
<h4>Version History</h4>
<ul>
<li><strong>0.8.0</strong>
<ul>
<li>Public release</li>
</ul>
</li>
</ul>
<h3>Links</h3>
<p>“<a href="http://www.web-strategy.jp/" title="CMS service with WordPress" rel="nofollow ugc">CMS service with WordPress</a>” provides you service that uses WordPress as a CMS.</p>
<h3>Special Thanks</h3>
<p>Translation:<a href="http://blog.dacelo.info/" title="Translation" rel="nofollow ugc">dacelo</a></p>


PS WP Multi Domain

PowieT

<p>Checks Domain WHOIS Lookup for availability. Simple insert the [pwhois] shortcode on a page or post.<br />
To select the default TLD use the default attribute: [pwhois default=com] – sets .com as default in the TLD dropdown.<br />
TLD List is limited because of the knowledge of the required whois servers. If you wish to have support for a special TLD please contact me and I will implement it asap.<br />
We cannot guarantee that every domain lookup works perfect, in case that whois servers and how to talk to them can change time by time.<br />
However if you inform us about changes and we can get it to work, we give you a free version of the Pro version of this plugin!</p>
<h4>Demos</h4>
<p><a href="https://powie.de/wordpress/whois/" rel="nofollow ugc">Demo 1</a> – at our own page.</p>
<p><a href="https://be-webspace.de/domaincheck/" rel="nofollow ugc">Demo 2</a> – live version at a hosting providers webpage.</p>
<h4>Requires</h4>
<ul>
<li>php7</li>
</ul>
<h4>Including:</h4>
<ul>
<li>Shortcode [pwhois]</li>
</ul>
<h4>Support</h4>
<p>Support Forum @ <a href="https://forum.powie.de/forum/87-powies-whois/" rel="nofollow ugc">forum.powie.de</a><br />
You get faster feedback if you post in our forum, rather than on wordpress.org!</p>
<h3>Remove plugin</h3>
<ol>
<li>Deactivate plugin through the ‘Plugins’ menu in WordPress</li>
<li>Delete plugin through the ‘Plugins’ menu in WordPress</li>
</ol>


Powie's WHOIS Domain Check

Not what I needed. It can only check availability for .com domains, not any TLD as in description. One star for inaccurate description.

LIMITED – only checks .com

Check a Domain WHOIS Lookup for availability. Simple insert the [pwhois] shortcode on a page or post

PS WP Multi Domain vs Powie's WHOIS Domain Check