Yes is possible. Simply connect a LAN cable from the Wingobox to the WAN port of the Asus, let the router take care of the rest (if necessary, make firewall adjustments) and then connect to the WLAN of the Asus.

Complete replacement of the Wingo Box is not possible. I deactivated the WLAN on my Wingo Box and connected the router to the Wingo Box via LAN. Then operate the router in access point mode. This should also be possible with devices from other manufacturers.