The chip firmware and driver are different, but we deliver both of those, and swapping between should be as simple as changing the MMHAL_CHIP_TYPE and FW_MBIN.
The mmhal_wlan abstraction layer for interfacing with the chip over SPI is agnostic to the chip and shouldn’t need to change.
For accessing the busy (and wake!) pin, I think your best bet is to use the test points around the chip - see here where I discussed this with another user: "mm8108-ekh05 v2" + esp32-p4 - #2 by ldennis