I got an answer this evening and I was told that there is a book on Eleonore Vergeot by Robert Lamouche with title "Eleonore Vergeot- Pour d'amour d'un Prince", published in 2005. I would like to order it, but there is the lack of the language. I won't understand it, I have to confess, but there seem to be much pictures, and maybe also some more of Eleonore.
I'll see, maybe also any other person is interested in the book. Unfortuntely there does not seem to be any English translation as the editor is a regional one.