Once you have set up your Joomla site to be multilingual and download the language for EasyBlog, you would have to create 2 different sets of blog posts for the 2 languages.
Then you have to associate these 2 posts with each other(Language filter plugin has to be enabled) so that when the user switches the site language, the blog post will change to the version associated with the language. You can refer to the documentation below.
I installed the language (German) for EasyBlog, but is no language section on the post. Please advice me. The languages (en, de, fr) appearing in the filter, bu no choice in a post for language.