Hi Nessler, sorry for the late reply.
Tell me if it works for you
<div id="meta-coauthor">
<span class='metacoauteur'>
<?php
$values = get_field('coauteurs');
if($values) {
foreach($values as $value) {
$author_ID = $value['ID'];
$author_url = esc_url( get_author_posts_url($author_ID) );
echo ', <a href="'.$author_url.'">' . $value['display_name'] . '</a>';
}
};
?>
</span>
</div>