No reaction to the question, neither positive nor negative.

I might be that it was poorly phrased!

As to now (V8) It is not possible to embed  any Rss source into the blog pages.

Of course one can copy and paste some content (once you have made the content field available into the blog post form view!)

My conclusion is that the currently released model for the Odoo blog is not at the maturity level of the major ones.

This will lead us to implement another blog solution.