Network interfaces on windows systems have several parameters that can be used for naming it: name of interface, name of adapter, alias of interface, maybe etc.
Now zabbix_agentd for windows recognize only the name of adapter and use it for networks monitoring (in items net.if.in, net.if.out, net.if.total and net.if.discovery).
In some cases when windows networking is quite complex than using only one physical interface it will be appropriate to use other interface parameters to discovering and monitoring network interfaces. One example was given in zabbix forum here - https://www.zabbix.com/forum/showthread.php?t=48799
I propose to add at least one attribute - name of interface - in network interfaces discovering for windows systems and give the ability to use it in items net.if.in, net.if.out and net.if.total