add_filter('acf/format_value/field_name=YOUR_FIELD_NAME_HERE', 'YOUR_FUNCTION_NAME_HERE', 20, 3);
YOUR_FUNCTION_NAME_HERE($value, $post_id, $field) {
$terms = wp_get_post_terms($post_id, 'YOUR_TAXONOMY_HERE');
if (!is_wp_error($terms) && !empty($terms)) {
foreach ($terms as $term) {
if (get_field('YOUR_FIELD_NAME', $term)) {
$value = get_field('YOUR_FIELD_NAME', $term);
}
}
}
return $value;
}