你可以劫持$query 就在拿到帖子之前。

function wpdev_156674_pre_get_posts( $query ) {

    if (
        $query->is_main_query()
        && $query->is_tax( \'region\' )
    ) {
        // Manipulate $query here, for instance like so
        $query->set( \'orderby\', \'meta_value_num\' );
        $query->set( \'meta_key\', \'event_date\' );
        $query->set( \'order\', \'DESC\' );
    }
}
add_action( \'pre_get_posts\', \'wpdev_156674_pre_get_posts\' );

References:

• pre_get_posts 动作挂钩WP_Query 等级