Hi,
I got Big Sur up and running using Jake's bootpack here:
Everything seems to be working perfectly with the exception of the headphone jack. It's just static when I plug in headphones. The audio icon changes to headphones, so I think the OS recognizes that I have something plugged in. I updated Lilu, AppleALC, and CodecCommander kexts and reset NVRAM. I'm not sure what else I can try to address this.
When I had Catalina on Clover, the ALC_fix worked. I'm not sure how to adapt that fix to OpenCore.
I can't attach my EFI folder since it's larger than 19.53MB, but it is mostly unchanged from Jake's guide with the exception of the three kexts I mentioned above.