Straight/crossover I knew what I meant 
In this post How to use wifi and lan? - #15 by sam_nazarko Sam talks about
sam_nazarko
Jul '16
nevercomeback:
You almost got me. The wifi interface with DHCP for internet, the wired interface with static IP for NAS. Both used at once.
Configure WiFi. Unplug it.
Configure Ethernet.
Plug both in.
To enable both at once:
sudo connmanctl
scan wifi
You’ll get a list of services.
Add connmanctl connect … to /etc/rc.local.
So it certainly sounds doable and easy.
I’m also investigating whether I can just plug the Pi and qNAP into the same powerline unit that the traffic doesn’t go out over the power line, this would be simpler and keep the traffic ‘closer’.