Honestly you're better off getting a non-wireless router and switch with sfp+ ports and back hauling them with 10gb transceivers, then just get a wifi6e AP. Microtik makes a real nice set of switches with dual sfp+ and multiple 2.5gbe ports.
Negotiating 5 gigabits was widely skipped to 10gb, which has more support than even 2.5gb.
Or skip learning what that all means and just get a wifi6e router with a 2.5gbe wan.
The BEST WAY? Run an Ethernet cable from your main router's lan port to a simple unmanaged network switch, then run a cable from the switch to the basement, to a new router. Name the router the same SSID(wifi name) as the main router, same password. Wired mesh done. Router models don't usually need to be the same.