你需要加入image_send_to_editor 滤器这允许您修改将图像插入内容编辑器时使用的标记。

像这样的方法应该会奏效：

add_filter(\'image_send_to_editor\', \'my_add_rel_nofollow\', 10, 8);
function my_add_rel_nofollow($html, $id, $caption, $title, $align, $url, $size, $alt = \'\' ){

    // check if there is already a rel value
    if ( preg_match(\'/<a.*? rel=".*?">/\', $html) ) {
        $html = preg_replace(\'/(<a.*? rel=".*?)(".*?>)/\', \'$1 \' . \'nofollow\' . \'$2\', $html);
    } else {
        $html = preg_replace(\'/(<a.*?)>/\', \'$1 rel="\' . \'nofollow\' . \'" >\', $html);
    }
    return $html;
}