For those still running Win98SE out there, there apparently are only very few USB adapters out there that still have driver support. Most of these adapters are outdated by now (old chips) and no longer sold. My machine had a busted onboard NIC and no free PCI slots, so USB seemed the only option left.

I had seen a few threads around mentioning the AX88772, so I got ahold of a cheap AX88772B adapter called "U2LAN". Turns out that the AX88772B isn't compatible with the final official Win9x AX88772(A) driver from '05. It just doesn't receive packets even after changing the INF.

Just couldn't leave it at that, so I patched the original Win9x driver and made it compatible with the AX88772B. Published the driver here along with a little guide on what had to be fixed for those interested: https://github.com/ijsf/AX88772B_WinME98SE

Took me quite a bit.. but was worth the challenge. With SMB 1.0 it just makes these Win98 machines pretty easy to access. The upside is that these B adapters are cheap and still being produced today, giving some viable options for easy USB ethernet on Win98SE for any machines that have proper USB drivers.

Finally got a chance to contribute something here. Hopefully it'll be useful to somebody!