An example to save submitted content as a post
add_action('wpcf7_mail_sent', 'hoge_wpcf7_insert_post', 10, 1);
function hoge_wpcf7_insert_post(){
$submission = WPCF7_Submission::get_instance();
if ( $submission ) {
$formdata = $submission->get_posted_data();
$email = $formdata['your-email'];
$name = $formdata['your-name'];
$new_post = array(
'post_type' => 'post',
'post_title' => $formdata['your-email'] . ' ' . $formdata['your-name'] ,
'post_status' => 'draft',
'post_content' => $formdata['your-message']
);
$post_id = wp_insert_post( $new_post );
// insert as post meta
add_post_meta( $post_id, 'some_meta', $formdata['some_meta']);
}
}