No way for us to know from here, as we don't have access to your network.
You'd have to take stock of all your connected devices, identify their MAC IDs and IP addresses, and compare them to the unknown devices.
The above devices just showed up on my iphone as connected to my XFI home network. What are they and should I work to delete them?
Any chance you have a Dell Inspiron 7773?
And do you have any Espreesif WiFi IoT / Smart Home / Smart Plug devices ?