Hello Wim Guiking.

I am really sorry because in easyblog 5, we don't this setting to restrict user from edit their own blog post.

But you can tweak some code in ...\components\com_easyblog\themes\wireframe\blogs\admin.tools.php file.

Change this code

<?php if (EB::isSiteAdmin() || $this->acl->get('moderate_entry') || $post->isMine()) { ?>

to this

<?php if (EB::isSiteAdmin() || $this->acl->get('moderate_entry')) { ?>

Hope this help