Nick van de Veerdonk

An HTML sitemap is a list of names and links of your pages and posts in the front end of your website. It can be useful for users to get a good overview of the content you’re presenting. For bots it is equally useful since the internal links send them to the farest corners of your website, which could help indexation greatly.
Strictly taken AMP does not need a sitemap (HTML or XML) if the content is marked up correctly: engines know where AMP content is by this piece of code present in your regular pages:
<pre><code><link rel="amphtml" href="https://www.example.com/url/to/amp/document.html">
</code></pre>
That being said there could be several reasons to use an AMP HTML Sitemap:
<ol>
<li>
You want your AMP content to be indexed faster and more regulary. In case you don’t have much traffic, external links or good internal linking structure indexation could take a while. An HTML sitemap will improve your internal links and if you add the URL of the sitemap to your current XML sitemap plugin, search engines will gain information on the AMP content by automatic submission of your XML sitemap. (see ‘Addditonal tips’ under installation tab)
</li>
<li>
You have ‘stand alone’ AMP content. Seen as there are no links pointing to content that is only reachable by AMP (because they miss the link from the regular page and naturally don’t occur in menus) it can take a long time for them to be indexed.
</li>
<li>
You have an HTML sitemap for regular content and simply wish to add your AMP content to it
</li>
</ol>
And in that case, this lightweight plugin is for you.
This plugin will not be supported, I will however try to answer all question in the comment section of the <a href="https://jaaadesign.nl/en/blog/amp-sitemap/" rel="nofollow ugc">plugin website</a> and create a FAQ.
Matt Cutts on HTML and XML sitemaps 
<iframe class="youtube-player" width="640" height="360" src="https://www.youtube.com/embed/hi5DGOu1uA0?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation"></iframe>

AMP HTML Sitemap

Only four stars so far, because although the description  says it does posts and pages, I only get posts.

This plugin worked well. After adding the shortcode to my existing sitemap page, there were new links appended with /amp to the AMP posts.  

Great idea for a plugin, and I just now submitted the sitemap page to "Fetch as Google" in the Search Console. I can't yet say if it will speed up Google's  discovery, but I do suspect it will.

***Update*** 
In 24 hours, AMP pages in Google's index went from "none found" for three domains, to well over 50%.  Clearly this plugins does what it's intended to do - helps Google get AMP pages indexed faster.

Worked Perfectly

The links have incorrect endings.
Should be:
site.url/stat-name.html

Actual result:
site.url/stat-name.htmlamp

The links have incorrect endings

Generates a customizable list of your AMP posts, pages and custom post types for SEO/indexing benefits, to be added to the content by shortcode.

Mohsin Rafique

Pixelative

Automagically add Accelerated Mobile Page <a href="https://www.ampproject.org/" rel="nofollow ugc">Google AMP Project</a> functionality to your site. Make your site load 5X faster on mobile by using features of the open source AMP project.
<a href="https://demo.ampwp.io/amp/" rel="nofollow ugc">Online Demo</a> | <a href="https://mailchi.mp/24a568511ae5/amp-wp-cf7" rel="nofollow ugc">AMP WP – Contact Form 7 Premium Extension</a> | <a href="https://help.ampwp.io/" rel="nofollow ugc">Support</a>
<h3>Features</h3>
FREE Features Include: 
* Gutenberg Support 
* Slider Support 
* AMP WP Powerful Settings Panel 
* AMP WP Options Panel 
* Sidebar 
* Related Posts 
* Layout – Classic View/ List View 
* Translation Panel 
* Site Loads 5x Faster in Mobiles 
* Full Google AMP Support 
* 100% Valid AMP Contents 
* 100% RTL Compatible 
* 100% Yoast SEO Compatible 
* Auto Ads For AMP Support 
* Compatible with All Cache Plugins 
* Compatible with Jetpack plugin 
* Notice Bar 
* GDPR Compliant (Europe Region) 
* Third Party Analytics to Track Visitors (Google Analytics, Facebook Pixel, Segment Analytics, Quantcast Tracking, Alexa Metrics, Chartbeat Analytics, comScore, Yandex Metrica, AFS Analytics, Adobe Analytics) 
* Native AMP Search Functionality 
* Show/Hide AMP Mobile Redirections for Mobile Visitors 
* Show/Hide AMP on Search Page 
* Show/Hide AMP feature on Post Types 
* Show/Hide AMP feature on Taxonomies (Categories/Tags/Custom) 
* Show/Hide Author in Archive Page 
* Show/Hide Date in Archive/Single Post Page 
* Show/Hide Author in Archive/Single Post Page 
* Show/Hide Thumbnail in Related Posts 
* Show/Hide Date in Related Posts 
* Show/Hide Author in Related Posts 
* Show/Hide Date in Home Page Slider 
* Show/Hide Author in Home Page Slider 
* Show/Hide Tags in Single Post Page 
* “Automattic AMP” Plugin Compatibility 
* Recent Comments 
* Sticky Header 
* AMP WordPress Menu 
* Custom AMP FrontPage 
* Social Icons 
* Embed Images, Videos, Audios and IFrames (YouTube, Vimeo, Vine, Twitter, Facebook, SoundCloud, Instagram). 
* Internal AMP Linking 
* Lightbox for Images 
* Enable/Disable AMP for Any Post 
* Customizable Color Scheme 
* Custom CSS Options 
* OneSignal Push Notifications integration 
* Contact Form 7 Support
<h4>Credits</h4>
<ul>
<li>
<a href="https://wppb.me/" rel="nofollow ugc">WORDPRESS PLUGIN BOILERPLATE GENERATOR</a> by Tom McFarlin, Inc., (https://twitter.com/tommcfarlin/) 
License: <a href="https://www.gnu.org/licenses/gpl-2.0.html" rel="nofollow ugc">Distributed under the terms of the GPLv2</a>
</li>
<li>
<a href="http://necolas.github.io/normalize.css/" rel="nofollow ugc">normalize.css</a> 
License: <a href="http://opensource.org/licenses/MIT" rel="nofollow ugc">Distributed under the terms of the MIT License</a>
</li>
<li>
<a href="https://fonts.google.com/specimen/Karla" rel="nofollow ugc">Karla</a> by Jonathan Pinhorn 
License: <a href="http://scripts.sil.org/OFL_web" rel="nofollow ugc">Open Font License</a>
</li>
<li>
<a href="https://fonts.google.com/specimen/Noto+Sans" rel="nofollow ugc">Noto Sans</a> by Google 
License: <a href="http://scripts.sil.org/OFL_web" rel="nofollow ugc">Open Font License</a>
</li>
<li>
<a href="https://fonts.google.com/specimen/Overpass+Mono" rel="nofollow ugc">Overpass Mono</a> by Delve Withrington 
License: <a href="http://scripts.sil.org/OFL_web" rel="nofollow ugc">Open Font License</a>
</li>
<li>
<a href="https://fortawesome.github.io/Font-Awesome/" rel="nofollow ugc">Font Awesome Free 4.7.0</a> by Dave Gandy 
Font License: SIL OFL 1.1 
Code License: MIT License 
<a href="https://fontawesome.com/license" rel="nofollow ugc">License</a>
</li>
</ul>
<h4>Translators</h4>
Please contribute to translate our plugin. Contact at <code>contact@ampwp.io</code>.
<h3>Minimum Requirements</h3>
<ul>
<li>Install <a href="https://wordpress.org/plugins/regenerate-thumbnails/" rel="ugc">Regenerate Thumbnails</a> and regenerate your post thumbnails to avoid breaking the layout on post list.</li>
<li>PHP version 7.4 or greater</li>
<li>MySQL version 8 or greater OR MariaDB version 10.5 or greater</li>
</ul>
<h3>Automatic Installation</h3>
Automatic installation is the easiest option as WordPress handles the file transfers itself and you don’t even need to leave your web browser. To do an automatic install, log in to your WordPress admin panel, navigate to the Plugins menu and click Add New.
In the search field type “AMP WP” and click Search Plugins. Once you’ve found the plugin you can view details about it such as the point release, rating and description. Most importantly of course, you can install it by clicking Install Now.
<h3>Manual Installation</h3>
This section describes how to install the plugin and get it working.
<ul>
<li>Download the plugin file to your computer and unzip it.</li>
<li>Using an FTP program, or your hosting control panel, upload the unzipped plugin folder to your WordPress installation’s <code>wp-content/plugins/</code> directory to your web server.</li>
<li>Activate the plugin through the ‘Plugins’ from menu in WordPress admin panel.</li>
<li>Use the AMP WP -> Customize AMP screen to configure the plugin</li>
</ul>

AMP WP – Google AMP For WordPress


Why can't you use your own theme?  Only have one very ugly theme doesn't work for me. Sorry.


Where do I start?

Automagically add Google AMP functionality to your site. Tons of Premium Features for FREE. Show/Hide Post Types, Categories, and Tags.

AMP HTML Sitemap vs AMP WP – Google AMP For WordPress