Thank you all! I finished move to OpenCore and BigSur.
At the moment, fixed all issues actual for me except 4k@48Hz.
This config is a compilation of the config from the first post and
@slipanot config
What is added or changed:
1.alcid = 16 - need to work 2.1 speaker with subwoofer
2.alc-verb_jack_fix - fix hotplug headphones jack
3.enabled ssd trim by deafult
4.changing igpu device property (4k@60Hz on Catalina, 4k@48Hz on Big Sur)
5.SSDT-DGPU.aml - Nvidia dGPU off
6.SSDT-BTNB.aml - Backlight fn buttons work together with patch:
change Method _Q80 to XQ80, pair with SSDT-BTNB.aml
change Method _Q81 to XQ81, pair with SSDT-BTNB.aml
Not tested and not used by me:
1. Built-in card reader (before I used Sinetek-rtsx.kext but stability and speed did not suit me)
2. HDMI port
3. DRM on Safari
Also I disabled SMCDellSensors.kext as it causes sound lags for me.