replying to myself here, but also, if this where supposed to work, which I doubt it will because it’s not feasible with tcpip, your second router would need to have the first router as gateway, but that is not possible when they are on the same subnet, and also your router will most likely not allow it because nat/routing will break, but if this was possible, devices behind your second router would not be able to connect to the devices before and vice versa, because since they have the same subnet, the traffic is considered local and not going through the router, and therefore the will not see each other as the NAT provides a separation between the networks…

you cannot use a router as a switch without using routing and different subnets … so … you might want to reconsider your design