From the version 1.5.0, with JW Player for WordPress plugin is possible to choose if using the self hosted version of the player, detailed information described here, or the Cloud Hosted Player Libraries, an easier and quicker method to start publishing our videos.
Cloud Hosted Player Libraries
Let’s see how we can get the player directly from the JW Player official site.
First of all, we need an account. If you don’t have one, you can register going to https://www.jwplayer.com/sign-up/.
Pricing information here:
https://www.jwplayer.com/plans/
After that, we just need to login and, from the dashboard, click on the Players button on the left.
https://dashboard.jwplayer.com/#/players

Clicking on the player we want to use, the Cloud-Hosted Player Library is well displayed at the bottom of the page.

We need to copy this URL and to paste it into the Plugin library URL field, in the plugin options page.
Important: No JWP License Key is required in this case.

To take full advantage of the plugin functionalities, add your API credentials following these instructions.