Eirudo

Embed YouTube videos and keept their aspect ratio, just using simple shortcode.
<ul>
<li>Simple shortcode, can be used in the posts or widgets.</li>
<li>Using default YouTube Embed Code (iframe), but make it responsive</li>
<li>Custom aspect ratio, if you want set different porpotion size.</li>
<li>Auto centered position. So if you insert it on your post section, the video always on center-aligned.</li>
<li>Lazy Load supported.</li>
<li>100% Free! And no ads or even trackers inside.</li>
</ul>
<h3>Arbitrary section</h3>
<h3>A brief Markdown Example</h3>
Pros: 
1. Simple, only using shortcode to use for individual video each shortcode 
2. Lazy Load supported 
3. Custom parameters for advanced use
Cons: 
1. Only for simple use,not for advanced playlist. Embedding one video for each shortcode.

Simple YouTube Responsive

Perfect

You can add a line to your functions.php to make videos responsive if you're doing your own theme. However, if you're not, this plugin works beautifully and gives other options like lazy load, etc. 

If doing your own theme, add: add_theme_support( 'responsive-embeds' );

Works Beautifully

Embed responsive YouTube videos using simple shortcode. Lazy Load supported.

Alec Rust

Gutenberg block and Shortcode for embedding YouTube/Vimeo videos, in a way that prevents users easily accessing the underlying video.
This is useful for example when embedding an “unlisted” video as premium course content behind a paywall on your site.
Features include:
<ul>
<li><a href="https://plyr.io/" rel="nofollow ugc">Plyr</a> player used to overlay default player with custom controls</li>
<li>Player modifications to always prevent clicking the default player</li>
<li>Encodes video ID in HTML to prevent finding it via “View Source”</li>
<li>Settings page to e.g. configure the player theme to match your site</li>
</ul>
<a href="https://protected-video.alecrust.com/" rel="nofollow ugc">View Player Demo</a>
Note: This only provides a basic level of protection. Technical users may still be able to access the underlying video.
This plugin is open source and contributions are welcome <a href="https://github.com/AlecRust/protected-video" rel="nofollow ugc">on GitHub</a>.

Protected Video

Very useful innovation for the course building community!

Makes YouTube More Usable in Online Courses

Thanks, Alec for the great work, a very useful plugin!
You deserve a million 5-stars reviews!

A very useful plugin

YouTube/Vimeo player that prevents easy sharing of the video.

Simple YouTube Responsive vs Protected Video