Please have a look to my settings :-) I hope this will help!
I am using a tp-link wr-1043nd router with OpenWrt. OpenWrt is open source and works with a lot of different routers. For more information read the OpenWrt documentation. https://openwrt.org/docs/start
The WAN input is connected to my internet router (yellow cable) and got the ip address 192.168.0.53. The DHCP service is configured with an static ip address 192.168.1.1 for the LAN and for the WLAN coming out of the OpenWrt router.
The MoodleBox is connected to a LAN port of the OpenWrt router (red cable). The DHCP is configured to set a static ip address 192.168.1.100 to the MoodleBox. The DNS is configured to assign moodlebox.home to 192.168.0.100. Every other computer, tablet or smartphone which is connected to the router LAN or to the router WLAN will get the DNS service. In your internet browser you can call the MoodleBox with the url moodlebox.home or the ip address 192.168.0.100 ... and I think that you can connect a lot of clients to the router.
You still can connect to the MoodleBox WLAN with the ip addresses 10.0.0.x.
Best regards, Ralf