This was mentioned in chat and it looks interesting:
What is Princeton IoT Inspector?
An open-source desktop tool with a one-click install process
Automatically discovers IoT devices and analyzes their network traffic
Helps you identify security and privacy issues with graphs and tables
Requires minimal technical skills and no special hardware
Use it to quickly inspect devices (e.g., from your computer) or continuously monitor your network (e.g., from a Raspberry Pi)
Related Twitter thread: