Hey there.
Are you sure what you're trying to do is possible at all?
If you really want to "bypass the NAT", you need to wire your PS4 directly to the WAN port. This means: It needs to get a unique IP address from your ISP. And this only works if your ISP provides you with more than one IP. Which most ISPs don't do.
If you're sure: Off we go.
Open the wireless configuration section of your OpenWRT router.
Add a new wireless interface. Pick an SSID that is distinct from the one you already have.
At the "Network" part, check the box of your WAN port.
No connect your PS4 to the new SSID.
But once again: I doubt that will work, because I really doubt your ISP gives you more than one IP address.
[edit]
Ah. And that has *nothing* to do with DMZ.
And the usual DMZ configuration does *not* bypass NAT.
So overall one must ask: What for?
Regards,
Stephan.
(Last edited by golialive on 23 Jun 2017, 11:56)