openvpn-monitor is a simple python program to generate html that displays the status of an OpenVPN server, including all current connections. It uses the OpenVPN management console. It typically runs on the same host as the OpenVPN server, however it does not necessarily need to.

So OpenVPN has a "management interface" thing where it listens on a port and you can get status information through that. I believe pfsense uses this for it's own status information and I bet you can also run this. I am going to mess around with this myself and I will let you know what I find. Monitoring/correlating traffic to VPN sessions - OpenVPN May 13, 2019 OpenVPN Alternatives and Similar Software -

VPN Gateway: VPN client for P2S OpenVPN protocol

OpenVPN Manager is a tool which controls OpenVPN. It is written in C# and uses the new management interface of OpenVPN . Use the smart card feature in a simple way, enter passwords, monitor the OpenVPN log etc Monitoring VPN connections | NetBeez Network Monitoring

Free Openvpn Monitor Downloads

Oct 15, 2019 OpenVPN for Kodi - Brian Hornsby The OpenVPN script can be accessed from the Programs menu or called using the RunScript builtin function (RunScript(script.openvpn)). The script can be passed the following arguments; e.g. RunScript(script.openvpn, Los Angeles).