The following code needs to be put inside your theme functions.php
/**
* @param $group_NAME
* @return array
*/
function fetchACFFields($group_NAME)
{
// Fetch fields for a given ACF fields group (PRO only)
$groups = acf_get_field_groups();
$fields_group = [];
foreach ($groups as $group) {
$title = $group['title'];
if ($title == $group_NAME) {
$f = acf_get_fields($group['ID']);
foreach ($f as $i) {
$fields_group[$group['title']]['fields'][$i['name']] = $i;
$fields_group[$group['title']]['fields'][$i['name']]['value'] = get_field($i['key']);
}
break;
}
}
return $fields_group;
}
add_filter( 'fetch_acf_fields', 'fetchACFFields', 10, 2 );
/**
* @param $fields_group
* @param $mysubfield
* @return array
*/
function fetchSubfieldChoices($group_NAME, $mysubfield)
{
$fields_group = apply_filters('fetch_acf_fields', $group_NAME);
// Find choices from subfield
$first_key = array_keys($fields_group)[0];
$root = $fields_group[$first_key];
$choices = [];
foreach ($root['fields'] as $subfield) {
foreach ($subfield['sub_fields'] as $sub_field) {
$sub_field_name = $sub_field['name'];
if ($sub_field_name == $mysubfield) {
$choices = $sub_field['choices'];
}
}
}
return $choices;
}
add_filter( 'fetch_subfield_choices', 'fetchSubfieldChoices', 10, 2 );
and then execute:
/**
$choices = apply_filters('fetch_subfield_choices', $group_NAME, $mysubfield);