JSON in oembed not being internationalized (using QTranslateX)

I have the same problem.
i’ve changed a bit, i’m no more a coder, the oembed.php file in the function get_oembed_response_data like this:

/**
 * Retrieves the oEmbed response data for a given post.
 *
 * @since 4.4.0
 *
 * @param WP_Post|int $post  Post object or ID.
 * @param int         $width The requested width.
 * @return array|false Response data on success, false if post doesn't exist.
 */
function get_oembed_response_data( $post, $width ) {
    $post  = get_post( $post );
    $width = absint( $width );


    $title = $post->post_title;
    $title = str_replace("[:it]","",$title);
    $title = str_replace("[:en]","",$title);
    $title = str_replace("[:]","",$title);


    if ( ! $post ) {
        return false;
    }

    if ( 'publish' !== get_post_status( $post ) ) {
        return false;
    }

    /**
     * Filters the allowed minimum and maximum widths for the oEmbed response.
     *
     * @since 4.4.0
     *
     * @param array $min_max_width {
     *     Minimum and maximum widths for the oEmbed response.
     *
     *     @type int $min Minimum width. Default 200.
     *     @type int $max Maximum width. Default 600.
     * }
     */
    $min_max_width = apply_filters( 'oembed_min_max_width', array(
        'min' => 200,
        'max' => 600
    ) );

    $width  = min( max( $min_max_width['min'], $width ), $min_max_width['max'] );
    $height = max( ceil( $width / 16 * 9 ), 200 );

    $data = array(
        'version'       => '1.0',
        'provider_name' => get_bloginfo( 'name' ),
        'provider_url'  => get_home_url(),
        'author_name'   => get_bloginfo( 'name' ),
        'author_url'    => get_home_url(),
        'title'         => $title,
        'type'          => 'link',
    );

    $author = get_userdata( $post->post_author );

    if ( $author ) {
        $data['author_name'] = $author->display_name;
        $data['author_url']  = get_author_posts_url( $author->ID );
    }

    /**
     * Filters the oEmbed response data.
     *
     * @since 4.4.0
     *
     * @param array   $data   The response data.
     * @param WP_Post $post   The post object.
     * @param int     $width  The requested width.
     * @param int     $height The calculated height.
     */
    return apply_filters( 'oembed_response_data', $data, $post, $width, $height );
}

Is not the solution but is just a workaround
Fabio