I don't think they made 10/100 cards for Nubus, if they did, it would be NuBus-90 compatible.

Be prepared for how SLOW the IIvx is. Despite having a faster 32Mhz CPU on paper and that fancy internal CD-ROM drive compatible case, its a real dog of a machine performance-wise (thanks Apple for the 16Mhz bus). The older 25Mhz IIci blows it away in speed....and leaves it in the dust....... oh wait.