You would have to use an acf/load_field filter or an acf/prepare_field filter.
In this filter you would have to use the field value $field['value'] which will hold an array of Post IDs. You would use this and do a WP_Query() using the value in the post__in argument and the ‘post_status’ argument set to ‘publish’ and replace the
field value with the IDs of the posts returned.
