Transparent Zerotier Gateway/Bridge

Hello, I would like to use Zerotier to remotely manage devices that are not running Zerotier. I have no prior information about the network to which the devices are connected. The solution I am looking for should therefore be independent of the target network and work with all networks.
I was thinking of a kind of transparent gateway on which Zerotier runs and which is connected between the device to be managed and the local network.
The device gets the IP address from the DHCP server of the local network exactly as if the gateway was not connected in between.
The gateway should make the gateway’s WebUI as well as the device connected to it accessible via Zerotier.
Since I use Teltonika RUT240 in other projects, I would also use this router for this solution, if possible.

Below is an overview picture of how I have imagined it. The IP addresses are examples and not known when setting up the gateway.

I would be very grateful for any tips and instructions.

Regards.

If you create this product, then I will buy it from you.