James Kemp

This plugin allows you to list any number of related posts from the same category as the current post. You can also randomise these results. It is very lightweight, at only 3KB.
There are a number of options available:
<ul>
<li>Choose the number of Posts to show</li>
<li>Choose whether it displays these posts randomly, or in order specified by you.</li>
<li>Choose whether to display a title, what tags to use, and what text should be displayed (e.g. H3)</li>
<li>Choose a class for the main UL</li>
</ul>
To display the random related posts in its simplest form, simply place the following code in your single.php file – <code><?php relatedPosts(); ?></code>.
To edit the options availble, use the following codes:
<pre><code><?php relatedPosts(
 $ppp = 4, 
 $rand = true, 
 $rPinctitle = true, 
 $rPtitletag = 'h3', 
 $rPtitle = 'Related Posts', 
 $rPulclass = 'related_posts',
 $orderby = 'title', 
 $order = 'ASC'
); ?>
</code></pre>
Where:
<ul>
<li>$ppp = Number of posts to display (Any integer allowed)</li>
<li>$rand = sets the display to random (true/false)</li>
<li>$rPinctitle = Displays the title (true/false)</li>
<li>$rPtitletag = The type of tag to wrap the title in (Default h3, but it can be any valid HTML tag)</li>
<li>$rPtitle = The title to be displayed (This can be any text value)</li>
<li>$rPulclass = This sets the class of the ul (This can be any text value)</li>
<li>$rPexcerpt = Displays the post excerpt (true/false)</li>
<li>$orderby = This allows you to order the posts by certain parameters (title/author/date/modified/menu_order/parent/ID/none/comment_count) If you want to choose the order of your posts, be sure to set $rand to false</li>
<li>$order = This can either be Ascending or Descending (ASC/DESC)</li>
</ul>

Random Related Posts Based on Category

This plugin allows you to list any number of related posts from the same category as the current post. You can also randomise these results.

WPClever

WPC Custom Related Products for WooCommerce is a super easy plugin for creating a custom list of recommended products on single product pages. It’s a simple but powerful tool for boosting cross-selling on your site.
By refining the related product list, store owners are entitled to promote products from the same collection or other product lines better, while making it easier for customers to find what they need easily or might be interested in. This, thus, offers a better chance for increasing order value and revenue.
<h4>Features</h4>
<ul>
<li>Enter some keywords to search & add products</li>
<li>Set default products from Up-Sells, Cross-Sells or both</li>
<li>Drag & drop to rearrange the order of items</li>
<li>Search configurations: search limit, search by SKU, exact or sentence search</li>
<li>Compatible with most common WordPress themes and plugins</li>
</ul>
<h4>Not what you needed?</h4>
Please try other plugins from us:
<ul>
<li><a href="https://wordpress.org/plugins/woo-product-bundle/" title="WPC Product Bundles" rel="ugc">WPC Product Bundles</a></li>
<li><a href="https://wordpress.org/plugins/wpc-composite-products/" title="WPC Composite Products" rel="ugc">WPC Composite Products</a></li>
<li><a href="https://wordpress.org/plugins/wpc-grouped-product/" title="WPC Grouped Product" rel="ugc">WPC Grouped Product</a></li>
<li><a href="https://wordpress.org/plugins/woo-bought-together/" title="WPC Frequently Bought Together" rel="ugc">WPC Frequently Bought Together</a></li>
<li><a href="https://wordpress.org/plugins/wpc-force-sells/" title="WPC Force Sells" rel="ugc">WPC Force Sells</a></li>
</ul>

WPC Custom Related Products for WooCommerce

WPC Custom Related Products allows you to choose custom related products for each product.

Random Related Posts Based on Category vs WPC Custom Related Products for WooCommerce