Razorfrog Web Design

This plugin creates a widget to display and link to WooCommerce products by category in a dropdown menu. Visitors to your site will have one-click access to products in your sidebar (or other widgetized areas) without valuable real estate being used up by a regular products list.
Plugin options include the abilities to:
<ul>
<li>display all products or just products in a single category</li>
<li>sort by product name, price, total sales, number of reviews, date published, date last modified, or random</li>
<li>limit the number of products shown</li>
</ul>
This plugin is also compatible with the <a href="https://wordpress.org/plugins/post-types-order/" rel="ugc">Post Types Order</a> plugin, so you can also sort by your own customized menu order if desired.
With these options you can use this plugin for a variety of uses. You could use multiple instances of the widget to have product dropdowns for each of your categories; you could display the top 5 most frequently bought products in a specific category; you could display the top 20 most reviewed products in your entire store or just in a specific category; and so on.
Note
For sites with a very large number of products, it is not recommended that you display all products in a single dropdown because it would be both heavy on server resources and also just be difficult to use.

Product Dropdown Widget for WooCommerce

Display and link to WooCommerce products in a dropdown menu widget. Allows for display of all products or products in individual categories as well as …

Blaze Concepts

Andrew

Display a list of all the products in a WooCommerce product category with this handy widget. Simply add the widget to a sidebar or widget area, customise the settings and your list is created.
<h4>Widget options include:</h4>
Title – Add a title to your product list. 
Category – Choose from a dynamically loaded drop down list of all WooCommerce product categories available on your website. 
Products Shown – Leave blank to show all products in the category or only show a certain number. 
Thumbnail – Show/hide the product thumbnail. 
Hidden Products – NEW! Show/hide Hidden products. 
Out Of Stock Products – NEW! Show/hide Out Of Stock products. 
Order By – Sort the list of products by Product Name, Product ID, Date Published, Last Modified, Random or None. 
Order – Display the list of products in Ascending or Descending order.

List Products By Category Widget for WooCommerce

Display a list of all the products in a WooCommerce product category with this handy widget.

Product Dropdown Widget for WooCommerce vs List Products By Category Widget for WooCommerce