WireGuard Server under main router and Network Mode setting

The instructions for setting up my WireGuard Server and client at this link:

were very helpful. I was able to get things running correctly. However I’m unsure about what Network Mode is best for my WireGuard Server: should it be Router, Access Point, or Extender? My Set up involves 3 routers. Two GL-MT3000 / Beryl AX (one at home and one for the road) and home main router. The main router port forwards to the first GL-MT300 (call it router B) . Router B is the one in question which is under the main house router. For the best performance what network mode should it be set to or does it matter?
** my main NightHawk R9000 router is not out of the box capable of running a WireGuard Server, hence the two Beryl routers.
Thanks!

So the Nighthawk is currently the Main Router upstream from the Beryl AX/WG Server?

To your question: WG usage requires routing tables ‘under the hood.’ The GL GUI sets that up all for you… so router mode it is.

Unsolicited advice: unless you need the Nighthawk to be between the ISP & the Beryl AX for some very specific reason, I’d turn the Nighthawk into an AP/dumb switch provided you can disable its routing/NAT capability. Use the Beryl AX as the primary/Main Router (eg: ISP → Beryl AX/WG Server → Nighthawk/AP+dumb switch → LAN/WAN clients).

Also, draw.io can help save your sanity when setting up routing/port forwarding, WG clients, etc.