Additional: there are a similar tools incorporated in Zabbix. You can use: net.tcp.service keys

I create this template for check connection between remotely hosts.

It can be useful to check connectivity specific host\port.

Supported Windows OS (need just powershell) and Linux OS systems (need NC app).

Windows - use PS script and userparameter

Linux - use NC app and UserParameter.

After implementation you can configure multi checks using  just Zabbix web interface.

Min Zabbix version - tested only 4.0.5 Zabbix, but i think it can be used in any version supported UserParameter.