Template App Nginx for Zabbix 4.0 that works without any external scripts.
You can poll Nginx using Zabbix agent locally(Template App Nginx Zabbix agent) or poll it directly from Zabbix server/proxy(Template App Nginx HTTP). Choose template that better suits you. Tune URL with user macros if required.
see https://nginx.ru/en/docs/http/ngx_http_stub_status_module.html