How add missing og: into 3th party component?

For the type, I'd recommend setting the default for that value in the Open Graph configuration area of JFBConnect:
type=website
That will set the type for all pages. In the upcoming 4.0 release, we'll be setting that as the default for all pages automatically.

For the image, you can do a few different things depending on what image should be used. First, we'd recommend setting a default value either way. The default image can be used if no other image is set, and at least great for making sure your logo is used or something else that represents your site.

Then, on each page, you can either use a Custom HTML module to insert the Open Graph tag with the best image for that page {JFBCGraph image=http://www.site.com/best-image-for-page.jpg} Other options are to create a template override for the component you're using and insert the JFBCGraph tag there, where you can add some PHP code to get best image from that page. I don't know anything about JomSport, so I wouldn't be able to help with that, but their support should be able to help you with a template override.

Hope that gets you started. If you need anything else, let us know!

Gregor,
Sorry for the delay in responding.

JFBConnect doesn't have the ability to automatically include the first image from any component as the Open Graph tag. For most components, this would have an undesired effect. Even for standard Joomla articles, the first image from the component is usually the pdf, email, or print icon. Special care is taken by JFBConnect to get the proper first image.

In whatever extension you're using, if there's any way to add text to the page (through the description or other similar area), we'd recommend adding the {JFBCGraph image=xxx} tag there per page. That will guarantee the best image is always used.

Hope this helps explain,
Alex