Stock routers used to share between WiFi and LAN for over a decade so you need to test this before you make changes to the router settings. As I don't have the router model and more important the router manual I will not be exact about the setting. The setting I look for is the firewall (set to off) and turn off client isolation.
I have a Windows 10 PC connected to my ISP's router (AT&T) with a CAT cable and a Windows 7 PC and Windows 10 laptop connecting via wi-fi. Without either plugging everything into the router or going 100% wi-fi, is there a way to network all three together so they are all visible to each other?
Also, (and I know this may be a long shot), I have 3 Android devices (a tablet and two phones). Is there a way to add them in the mix as well?

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