To solve this WiFi has RTS/CTS where nodes coordinate before transmitting.
Basically, if you have 3 nodes A, B, C, and A/C wants to talk to B, they send a request-to-send. Now B can coordinate the transmission order using clear-to-send.
Otherwise what can happen is A and C transmit at the same time and interfere.
MIMO is pretty common on recent phones Wi-Fi hardware, does that help? I know my last two pixels can create a Wi-Fi hotspot while connected to WiFi as the source network. I've no idea if that's part of the Wi-Fi direct standard though.
MIMO does help. But even with MIMO, almost all WiFi radios are single-channel operation.
The WiFi hotspot thing is possible with SISO as wellz
It basically uses the same channel to connect to the network and to host its own.
