Eirudo

<p>Embed YouTube videos and keept their aspect ratio, just using simple shortcode.</p>
<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>
<p>Pros:<br />
1. Simple, only using shortcode to use for individual video each shortcode<br />
2. Lazy Load supported<br />
3. Custom parameters for advanced use</p>
<p>Cons:<br />
1. Only for simple use,not for advanced playlist. Embedding one video for each shortcode.</p>


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.

woracal

<p>Add youtube vídeos to your WordPress blog with just a few clicks. Comes with features to brand each video with your logo.</p>
<p>Features:</p>
<ul>
<li>Add videos as a short code to your WordPress posts and pages easily.</li>
<li>Allows you to brand your WordPress videos with a logo on the top left or right</li>
<li>Option to dim the background while the video is playing</li>
<li>Settings for auto-play</li>
<li>Dark and light theme settings</li>
<li>Video border color settings </li>
<li>Show/hide controls</li>
<li>Auto hide control bar settings</li>
</ul>
<p>All options are easy to change in the admin area. No technical skills required</p>


Agile Video Player Lite

Makes adding videos to Wordpress blogs very easy. Just paste the video URL into the form, set size and other options and submit.

Simple YouTube Responsive vs Agile Video Player Lite