This is a network scanning tool that will log all the devices. It allows for manually naming and sends notifications via Discord webhooks.

It could be enhanced to use a routers API's to block unauthorized devices. This could be another fun project. If your router doesn't have API's available, you might need some new hardware. A PC with 2 ethernet ports running OPNsense as the router.firewall would be powerful and fun.

Topology

[Internet Modem] -> [OPNsense Router] -> [Network Switch] -> [Devices (AP, PCs, etc.)]