You should be able to use this filter to set the order and orderby parameters of the query. https://www.advancedcustomfields.com/resources/acf-fields-post_object-query/
Here is code from ACF that shows the defaults used
// defaults
$args = wp_parse_args( $args, array(
'posts_per_page' => -1,
'paged' => 0,
'post_type' => 'post',
'orderby' => 'menu_order title',
'order' => 'ASC',
'post_status' => 'any',
'suppress_filters' => false,
'update_post_meta_cache' => false,
));