I did confirm this as an unsupported workaround to add a I219-V NIC with vsphere 6.0 update 1
Use the ESXi Customizer tool from Andreas Peetz. VMware Front Experience: ESXi-Customizer-PS This loads an updated e1000e driver that contains a compatible driver for the Intel I219-V NIC. https://vibsdepot.v-front.de/wiki/index.php/Net-e1000e
It emphasizes it in the article, but I will emphasize it again, use the powershell command, not the GUI to create the ISO.
My Asrock Z170 motherboard with an Intel i7 6700K proc is up and running vSphere 6.0 update 1 with full network compatibility.