Can you provide a link to the manual?
But with routers being cheap as they are, I'm afraid the best - if not only - solution is to just buy a second router.
Kees
I have an ASUS RT-AC87U router that I'm trying to configure the following:
Run connect two WAN sources (DSL and 4G), each get used by one wifi SSID.
DSL connection used by Wifi_1
4G USB dongle used by Wifi_2
Is that setup possible?

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