While browsing the (unofficial) VMware Reddit this morning and came across a thread where the OP was asking for a recommendation on USB network adapters that can be used with ESXi with their Intel NUC, which many replied with their recommendations and a pointer over to the USB Network Native Driver for ESXi Fling, which would be required if you are using one of the supported chipsets.
The community already covered all the basics and I did not have anything to add until I saw the following comment:
To my knowledge at least, there are zero drivers for USB network interfaces without using a fling.
Although this was certainly true a few years back, that the only way for ESXi to see a USB network adapter was to first install the USB Network Native Driver, this is technically no longer accurate due to some recent enhancements with ESXi that may not be very well known.