Is there a way to embed video for free on optimize press ?

Looks like you just answered your own question?

Amazon S3 and EasyVideo are the paid alternatives OP suggests, but there is a free option also... it might be called JVMedia player, not sure, whatever it's called it's free and they provide it.

Two different things are being talked about here. Amazon S3 is video HOSTING and Easy Video Player, JW Player, Traffic Player, etc are all video players. You need both a video player AND video hosting to host your own video on your website.

There are free video players available. One such free player is: Download / Buy Flowplayer : Flowplayer

You need to download the script and follow the instructions to upload it correctly to your website.

The next thing you need to do is to host your video file somewhere. Technically you could just upload the file to your regular hosting server but the reason most people suggest you do not do this is because performance will suffer greatly if you get just a few people watching that video at the same time. Video puts a lot of strain on server resources.

For that reason most people nowadays use a separate host for files such as videos and downloads. One of the most popular is Amazon S3. It is DIRT cheap and you can literally have thousands of people watching your video at the same time and your performance will NOT suffer at all. This means your customers get to watch videos that ALWAYS download nice and fast and you get to relax in the comfort of knowing your web server won't collapse if a few people watch your video at the same time.

Quire frankly Amazon S3 is now considered the standard for this type of video hosting so I do suggest you set up an account and start using it if you are even remotely serious about your business. You only pay for what you use and the prices are ridiculously cheap.