Alkaweb

Add to your site a top-notch live search field.
Eonet Live Search can be added to any search field. 
It’ll create a nice popup box with the search’s result in real time. It plays very well with Buddypress, Woocommerce 
and any other custom post type. Specific integration can be added by us.
<a href="http://alka-web.com/eonet/live-search/" rel="nofollow ugc">Live Demo</a>
<h4>Featured features:</h4>
<ul>
<li>Options panel</li>
<li>Buddypress Members integration</li>
<li>Buddypress Groups integration</li>
<li>Buddypress Activities integration</li>
<li>Works with any custom post types</li>
<li>Pages / Posts integration</li>
<li>AJAX powered, no page reload</li>
<li>User search history</li>
<li>Options to restrain the search sections</li>
<li>Results listed within organized tabs</li>
</ul>
<h4>For developers:</h4>
<ul>
<li>Hooks/Filters available in all the plugin code</li>
<li>Minified files</li>
<li>Documented code</li>
<li>GPL license</li>
<li>Secure development using tokens and WordPress native functions</li>
</ul>
If you’re looking for a next generation live search plugin, you should give it a go!
We’re open to any feature suggestion.
This plugin has been developed as a side project by the Alkaweb developers team.

Eonet Live Search

It's an useful and pretty flexible plugin!

I like it

Search dynamically in real time through all your site, including pages, posts, members, products & so on.

Brainstorm Force

Pratik Chaskar

WP Remote Site Search is a search plugin for WordPress that returns any WordPress site’s data using WP REST API.
Basic Usage
Activate the WP Remote Site Search plugin 
Add the shortcode [wp_remote_site_search] to a page or something
Options
Here’s a list of shortcodes currently available in the WP Remote Site Search plugin.
1.<code>remote_url="https://example.com"</code>
<pre><code>URL from where you want to fetch the information
The remote site should have WordPress 4.7 or higher or Rest API (v2) plugin installed to get the search results.
</code></pre>
2.<code>title="How can we help?"</code>
<pre><code>Title for the search box
</code></pre>
3.<code>category_id="1,2"</code>
<pre><code>You can also pass "category_id1,category_id2" to search multiple posts from multiple categories.
</code></pre>
4.<code>sub_categories="true"</code>
<pre><code>You can also get all results from categories (category_id1, category_id2) and their respective subcategories by setting sub_categories="true".
</code></pre>
5.<code>placeholder="Enter a search term."</code>
<pre><code>The text displayed in the search box placeholder. Default is "Search...".
</code></pre>
6.<code>type = "books"</code>
<pre><code>Default type is posts,
You can add custom post type also.
</code></pre>
7.<code>max_results="50"</code>
<pre><code>Total Number of results you want to display.
(default max_results is 30)
</code></pre>
8.<code>html_input = "<button> Get In Touch!</button>"</code>
 Append html after all results get displyed.
Example:
<pre><code>[wp_remote_site_search remote_url="https://example.com" category_id="1,2" sub_categories="true" type="books" title="How can we help?" placeholder="Have a question? Enter a search term." max_results="30" html_input="<button>Get In Touch!</button>"]
</code></pre>
<h3>Credits</h3>
WP Live Search 
Licenses: GNU GPL, Version 2 (or later) 
Credits https://wordpress.org/plugins/wp-search-live/

WP Remote Site Search

Search any WordPress site's data using WP REST API.

Eonet Live Search vs WP Remote Site Search