Hi,
If the port is used, we can get kind of technology is used using Powershell.
For example, my laptop PC has standard monitor and 2 external monitors. One of external monitor is using HDMI. Another is using DisplayPort.
According following document (jump to microsoft site),
_D3DKMDT_VIDEO_OUTPUT_TECHNOLOGY | Microsoft Docs
5 = HDMI
10=DisplayPort
214783648(0x80000000) = Internal
Although you need to write a script to convert from the result to MIF file, you will manage the inventories on DSM Explorer. However, unused ports are not shown with this way. I'm not sure, but it maybe difficult to get them.
I hope my info helps you.
Regards
Yas