Traffic bill for Proxmox VM's

I’m new to LibreNMS and use it to replace Cacti and also like to use the Proxmox application/plugin functionality. All is working fine and I’m very pleased with how things work, it’s way more intuitive and modern than Cacti.
The traffic bill option is very useful for us and it works great for router/switch ports. Now I’ve setup Proxmox servers with the LibreNMS agent and SNMP and added a few of our servers to LibreNMS. All network interfaces of all VM’s are detected and graphing but now I would like to create a traffic bill for all our VM customers but that doesn’t seem to be possible? I can only select a device for a traffic bill followed by a port but in the case of Proxmox servers there aren’t ports selectable. How can I set this up?

Is it possible to use the Billing module for Proxmox interfaces? If not, is this on the roadmap? Thank you!