I am experiencing the same issue but not on all translated pages. However, it was quite easy to trace back to the lines of code that were causing this issue as the preview URL was just wrong.
By replacing lines
$wpml = CS()->loadComponent('Wpml');
$this->permalink = apply_filters( 'wpml_permalink', get_permalink( $post ), apply_filters('cs_locate_wpml_language', null, $post ) );
$this->permalink = get_permalink( $post );
everything works just fine. I would recommend to abstract the entire WPML functionality in a MultiLanguage class and then derive a WPML or Polylang Implementation from that, that can be loaded depending on which plugin is installed. I haven't looked into the details of the WPML implementation as the above works for me. Would be great if that could be integrated into the next release.