Abidemi Kusimo

You can make use of category popular tag to display most used tag on your blog. This will give list of frequently used tag anywhere you place the shortcode or funtion in your theme.
For example [popular_category_tags count=10 type=”popular-tags” category_id=”1″]. 
You can also call this function from your theme file: cush_category_popular_tag() for basic output.
When using the shortcode type is required. category id, count is not required. if no category id suplied, the plugin will default to current post category available. 
For example [popular_category_tags type=”popular-tags” ].
You can find category tags options under Settings page 
Settings -> Category Tags
Credit : (https://wordpress.stackexchange.com/questions/261617/display-most-popular-tags-of-category)

Category Popular Tags

Display popular tags on achieve/category page of your theme using sortcode or by calling a function.

MattGeri

WP Geeks

WP Most Popular was born out of frustration in finding a decent plugin which performs one simple task and that is to rank your most popular blog posts.
The plugin keeps a log of your most popular posts based on views and lets you display them in your blog theme with custom styling. You can display popular posts from the last day, 7 days, 30 days or all time.
It also comes with a sidebar widget to let you display your popular posts on your blogs sidebar.
If you are a developer and integrate the plugin in to a theme, you will get a lot more flexibility out of the plugin including the ability to show the most popular custom post types etc.
This plugin was built and is maintained by <a href="https://wpgeeks.com" rel="nofollow ugc">WP Geeks</a>. For extra documentation, videos, snippets and support, visit the <a href="https://wpgeeks.com/product/wp-most-popular/" rel="nofollow ugc">WP Most Popular</a> product page.
<h3>Usage</h3>
There are two ways in which you can use this plugin.
<ol>
<li>As a sidebar widget</li>
<li>Custom function in your theme files</li>
</ol>
Using the widget is the easiest way and recommended for most users. If you are a developer and want to integrate the plugin in to your existing theme, then read the information below.
Firstly, the main function which you will need to include in your theme to fetch the popular posts is called <code>wp_most_popular_get_popular()</code>.
You can pass that function the following parameters in array form:
<ul>
<li>limit (integer)
<ul>
<li>The number of posts you would like to display i.e. 5</li>
<li>Default: 5</li>
</ul>
</li>
<li>post_type (string) / (array)
<ul>
<li>The post type you would like to display</li>
<li>Example: post</li>
<li>Default: All post types</li>
</ul>
</li>
<li>range (string)
<ul>
<li>In what date range would you like to display popular posts in</li>
<li>Accepted: all_time, monthly, weekly, daily</li>
<li>Default: all_time</li>
</ul>
</li>
</ul>
Those are the current parameters that the plugin supports. Let’s look at an example of how to display the most recent popular posts in a unordered list.
<pre><code><?php
echo '<ul>';
$posts = wp_most_popular_get_popular( array( 'limit' => 10, 'post_type' => 'post', 'range' => 'all_time' ) );
global $post;
if ( count( $posts ) > 0 ): foreach ( $posts as $post ):
 setup_postdata( $post );
 ?>
 <li><a href="<?php the_permalink() ?>" title="<?php echo esc_attr(get_the_title() ? get_the_title() : get_the_ID()); ?>"><?php if ( get_the_title() ) the_title(); else the_ID(); ?></a></li>
 <?php
endforeach; endif;
echo '</ul>';
?>
</code></pre>
<h4>Filters</h4>
The following filters are available to you:
<ul>
<li>wp_most_popular_list_before – used to filter the </li>
</ul>
<ul> element of the outputted widget list 
* **wp_most_popular_list_after** – used to filter the </ul>
element of the outputted widget list 
* wp_most_popular_list_item_single – filters for a the list item generated by the widget
<h4>Actions</h4>
<ul>
<li>wp_most_popular_list_item – used for modifying the list output</li>
</ul>

WP Most Popular

Works just as expected :)
Triggers the stat update from JS on the frontend so it works with cache.

Great plugin

WP Most Popular is a simple plugin which tracks your most popular blog posts based on views and lets you display them in your theme or blog sidebar.

Category Popular Tags vs WP Most Popular