shazdeh

This widgets enables you to make dropdown menus. It doesn’t have any skins, but you can optionaly choose to load and apply Superfish’s default styles.

Dropdown Navigation Menus

A widget to create dropdown menus powered by jQuery Superfish.

Amin Nazemi

This plugin disables Pagination in navigation menu lists and preserves taxonomy hierarchy. 
Also, it helps you when you using WooCommerce and you have more than 50 category items. 
It can preserve WooCommerce category hierarchy.
FEATURES
<ul>
<li>Disable Pagination in nav menu add item lists </li>
<li>Preserve hierarchy in category nav menu add item list and posts category selector</li>
<li>Automatically scroll to first checked item in post category selector </li>
<li>Preserve WooCommerce category hierarchy</li>
</ul>

Preserve Taxonomy Hierarchy

Preserve hierarchy in posts category and navigation menu editor lists.

Dropdown Navigation Menus vs Preserve Taxonomy Hierarchy