Is this router technology available?

Are you trying to create a larger WLAN network?  One with a single SSID that allows the user to move seamlessly between radios?

If yes, then there are two ways to do it.  You can have a WLAN network created with a master controller (which is like a router) and have many "dumb" WLAN Access Points connected to it.  This is how they build WLAN networks in large environments with lots of users, like a shopping mall or sports stadium.  In this case all the access points are hardwired via Ethernet back the controller.The other way is to create what is known as wireless mesh network.  In this case you have a bunch of access points that communicate with a single controlling devices using WiFi to communicate between the mesh points.   https://www.pcmag.com/picks/the-best-wi-fi-mesh-ne... are large scale mesh systems from vendors like Cisco Systems.  The article above links to home mesh systems.

You are describing something like "mesh" systems.

It's not that rare for separate WiFi access points, but very few home routers have such a capability.

This is an article listing some available ones:https://www.expertreviews.co.uk/networks/1406868/b...

Also note you cannot simply cross-connect multiple routers with different internet connections - each tries to "take over" and provide sole internet access for any connected device, so they would conflict with each other.

Any such system needs a single point of connection or a central controller to coordinate connectivity between devices and gateways.

Routers can be "Daisy-Chained"    Ethernet Cable from LAN port on 1st router to WAN port on Second Router.

I am doing this at my Club.   Two Buildings.   Building 1 has the Lead In Cable going to the first WIFI/Router/Modem -  Then I ran a long Ethernet Cable from one of the LAN ports over to building Two and plugged it into the WAN port on Router two, which provides WIFI for that building and 4 LAN connections.

You can look for "wireless bridging". That is where one router is used as a "bridge" in that it connects to another router then put that network out on its own wired LAN.

You cannot use a regular router to connect to another, and have it also give off wifi at the same time. A wifi adapter in a router (most devices) is either a host (access point that laptops connect to) or a client (router connects to another wifi signal to link it to its LAN port)