Sorry, but I can't see the point.
I did the mentioned point a.
More in detail:
* I installed the native AppleHDA.kext (I think it's the native one. I did the update from 10.14.0 to 10.14.2. After this the size of AppleHDA.kext was different to the old version)
* I removed the entries from the config.plist. If I missed an entry please let me know which one.
* I removed the realtecALC.kext from kext/other
* I removed the realtecALC.kext from /L/E
... do I forgot something?
Point b should be that one (Because the Asrock Z370 extreme4 has an 1220 chip):
I described the problem with "No audio devices" - Ok, the HDMI audio is available but not the onboard sound.
OS X version is now 10.14.2, Asrock Z370 extreme, i7 8700k, RX580
I used multibeast 11 for installation
All necessary files should be in the attached zip file.
If I misunderstand something please let me know and I will send the correct information.
Many thanks