Add rel=”nofollow” to Author Bio in WP

Add this code on your functions.php.

function author_bio_seo() {
$the_author_description = get_the_author_meta('description');
$string = str_replace('href','rel="nofollow" href', $the_author_description);
echo $string;
}

And add this code where you want to show the author bio:

<?php author_bio_seo(); ?>