So I finally got one of the rarest and weirdest pc98 family machines, the NEC APC III. It's a localized PC-9801f for the anglosphere, with the PC codepage instead of a kanji ROM, ttl video I need to find out how to adapt, and a us layout keyboard with the same switches as the early pc98 keyboards.
There's unfortunately some battery corrosion that seeped into the 8087 socket but these things are so rare it's worth trying to fix and repair. I might end up letting someone else finish the cleanup work if the video out works on here. There's no beep but I heard the pi-po sound didn't come until the 9801VX.
On a related note, here's the APC III keyboard next to the final pc98 keyboard layout used in the windows era rubber dome keyboards. The keyboard layout didn't change too much from the early 9801 boards (see wiki pic), while the APC III has 12 function keys and keys removed/moved around (likely sharing similar scan codes) from both.
The keyboard uses the infamous linear NEC switches that when stored in the high humidity of Japan tend to break down and quit working.