If you are providing a compatible ethernet board as in this writeup, virtually anything you can actually plug the board into will work. Not to imply that OBSD does not support most ethernet, as opposed to WiFi where you might have to be a bit more selective. Here is the list of appropriate WiFi drivers that can be used to make a OBSD based access point:

* https://www.openbsd.org/faq/faq6.html#Wireless