SIP Devices in TAC
Have you noticed this in Teams Admin Center?
It's in public Preview. With this you can now do admin for your SIP devices who you might have connected to your SIP registrar on SBC.
Want to know more on how it can be done. Read this from Microsoft or contact your SBC provider if you have your own SBC in how to configure the Session Boarder Controller as a SIP registrar.
There are also partners out there who can provide SBCaaS (SBC as a Service) where they have SIP registrar as a running service.