How to play embedded video in jwplayer
 

Question is in the title...is this even possible?

I found some Kenplayer plugin that transforms video, may I use this on my tube site?

I have worked with jw player in the past, you will need the source file url, from jw player website you can insert the link in the player and create a embed code to that video.

Good luck

Yes it's possible, I've got the kenplayer and it basically takes the embed code and queries the tube hosting the video and parses out the source video, and then plug's it into the jw or videojs player.

One note of caution, once the primary tube changes the embed just a little it will break, so you have to keep and eye on your tubes all the time and turn off the plugin so it won't break all your posts. The other issue that I see is that your server is doing a query every time someone wants to view the video, so all the hosting tube has to do is to block your ip, and your tube won't work any longer either :1orglaugh

I tried with source URL and it didn't work, it shows "Error loading media". I have to find URL of mp4 video itself and to add it to jwplayer, but is this allowed?

If you use Wordpress, you can use these plugins:
https://wordpress.org/plugins/easy-video-player/
https://wordpress.org/plugins/fv-wordpress-flowplayer/

Yes, I tried both plugins but neither worked for embedded videos. I guess I will host videos on my server and play them with JWplayer, number of videos will be smaller, but in general, it's better for SEO, and content is definitely original than on all other major tubes, right? :)

Yes, self-hosted videos are better than embed ones ;)