kanedo

This widget displays all comments on all blogs on your multi site wordpress installation. You can define how many comments should be displayed.

Get All Comments Widget

Creates a widget which lists all comments across all sites of a multi site wordpress installation

CodingMall.com

This plugin allows you to make multiple front end websites from just a single, simple installation of WordPress.
Suppose you have a WordPress site example.com. It contains 100 posts. You want to show some of them on cars.example.com, some on my-super-domain.com and some posts on mobiles.example.com. See? you can show content across multiple subdomains and even on separate domains.
How to do it? Very simple. To setup a new subdomain for example cars.example.com, do the following:
<ul>
<li>
First point cars.example.com to your main website server. This may require changing of DNS records. On many hosting providers this process is called create a “Domain Alias”. The target is that if you browse your new domain or subdomain, it should show the content as you see on your main site.
</li>
<li>
Create a new ‘Contributor’ type user.
</li>
<li>
Put https://cars.example.com in site url field and save.
</li>
<li>
Now, go in Posts and set that author to those posts which you want to show on cars.example.com.
</li>
<li>
That’s all. Now browse https://cars.example.com and you will see posts made by the contributor user of this site.
</li>
</ul>
For more information or support, you can contact us at 
<a href="https://codingmall.com/contact-us" rel="nofollow ugc">https://codingmall.com/contact-us</a>
MORE FEATURES:
If you want to create a true Multisite experience and if you want more features, please have a look here; 
<a href="https://codingmall.com/wordpress/203-multi-sites-for-wordpress-and-woocommerce" rel="nofollow ugc">https://codingmall.com/wordpress/203-multi-sites-for-wordpress-and-woocommerce</a>
If you have a native WordPress Multisite Network, then use this version instead: 
<a href="https://codingmall.com/wordpress/216-easy-sharing-of-posts-pages-and-products" rel="nofollow ugc">https://codingmall.com/wordpress/216-easy-sharing-of-posts-pages-and-products</a>
You may get features like the following with the premium version:
<ul>
<li>Show a different page on home page</li>
<li>Setting up WordPress differently for each site. For example, different permalink style for each website</li>
<li>Having a different theme for each domain or subdomain</li>
<li>Showing a different menu on each site</li>
<li>Providing different Widgets on different sites</li>
<li>Want to use WooCommerce and create a Multi store, Multisite, Multi vendor website</li>
<li>Showing different products on each store or vendor site</li>
<li>Different WooCommerce settings for each store. For example, different shipping and tax rates for each store.</li>
</ul>
and many many more…

CM Multisite-Lite

Serve multiple front end websites with different content from a single WordPress installation.

Get All Comments Widget vs CM Multisite-Lite