rewrite ^/v3/list/([0-9-_a-z]+?).html$  /index.php?list_v3=$1 last;

add_rule('list/([0-9-_a-z]+).html$', 'index.php?list_v3=$matches[1]', 'top');

rewrite ^/list/([0-9-_a-z]+?).html$ /index.php?list_v3=$1 last;