Once you have one of the lookup sites open paste the complete MAC address in and it may if you are lucky list the actual name of the device the address belongs to. Rather than the generic component makers name.
Like in first image. The MAC belongs to a Panasonic Blu-ray player on the network.
The second shows the way it's displayed in the router.
The second is from my router, a FritzBox. Different makes of routers will display things differently. It's been about 10 years since I used a hub so don't know how detailed their network lists are. The connected devices should be listed under My Devices on the Hub 6, going by a quick look at the manual.
I don't see those those unknown networks on my devices on my bt hub 6 am a bit worried now?
If nothing odd is showing as connected to your hub then you have no problems.
The image below shows an 'unknown' network device (MAC highlighted) it belongs to some neighbours Google Chromecast. I guess your security software is finding loads of nearby devices. Though as none are connected to your network you have no worries.
Silly me. Only two images on desktop and I click the wrong one. Apologies.