How to create many similar Zabbix nodes with graphs and network interfaces?

Question

Zabbix

Colleagues, now I am configuring the monitoring server, for monitoring the same type of hardware (sorry for the tautology). Each piece of iron will have 16 network interfaces. Of these, 4 modems and 4 VPNs. Moreover, the number can be variable, since the modem and / or VPN may fall off. The final piece of iron works on centos 7 and there is an agent on it, with the same type of config.
The task is to quickly add a new piece of hardware to a new server, creating a ready-made complex screen for it. But I ran into a number of problems. The first problem is that monitoring of network interfaces does not start immediately, but after some time (calculated in hours). At the same time, if there is no interface, for example, one vpn is not raised, then, accordingly, it is not added to the monitoring. Here, for example, are two completely identical pieces of iron, which have a different number of interfaces.
The question is how hard to set the monitoring of network interfaces, regardless of its physical presence at the moment on the piece of iron?
For example, here is a screenshot from the first host, on which everything works correctly and all VPNs are up (the user parameter is underlined in green - these are the temperature parameters and the lifted tunnel, which will not be on the second piece of hardware) All these "Network interface discovery:" change dynamically, which OoOoOoooOochen inconvenient for scaling. We need strict clarity! Interface names are known in advance.

On the second piece of iron this interface is absent.

That's it, that means we can't create a tunnel and modem monitoring chart on the same chart.

Likewise, the question: how to transfer custom graphs from one node to another. Do I need graphs so that there are tunnel interfaces on the graph with a modem (vpn is tied to a specific host)? When trying to create such a chart by hand on the second piece of iron, it was said that such a template already exists.
In which direction should you move? The ambiguity with network interfaces and graphs just infuriates ...