Configure WireGuard to only route local LAN traffic

In the client configuration, simply change the AllowedIPs from:

AllowedIPs = 0.0.0.0/0, ::/0

To the private address range, for example:

AllowedIPs = 192.168.0.0/16
# Or if you want to be more specific
AllowedIPs = 192.168.1.0/24