Updated the article with new information
For graphics: dgVoodoo 2.54 (http://dege.freeweb.hu/dgVoodoo2/dgVoodoo2/); put x86 version of D3D8.dll in the game folder. dgVoodoo, latest version can also be used. You must set "Output API" to Direct3D 12 with an updated AMD card and all should work.
For audio: DSOAL latest (http://vaporeon.io/hosted/dsoal-builds/); put all 3 files in the game folder.
So this is just something to answer myself, but also other players still trying to figure out how to get GR working on Windows 10/ 11 with great graphics and audio.
The original installation media for GR has DRM. You can go to GOG to grab a copy of DRM-free Ghost Recon. In you don't want to buy this one but have the original installation media there are instructions available on this forum to get it working like that as well.
The bloom effect mod from ENB series seems to not natively do 32-bit Z-buffer. It looks a little that the option doesn't get exposed properly. No worries, since there is something called dgVoodoo2 that actually is capable of exposing this option properly so you can set it in-game. Using dgVoodoo2 for AMD graphics cards owners that update their drivers also resolves that annoying MiniDumpWriteDump error for the atiumdag.dll file.
Get dgVoodoo2; either 2.54 or latest version: http://dege.freeweb.hu/dgVoodoo2/dgVoodoo2/
Extract the archive
Place D3D8.dll from the x86 folder (since this is a 32-bit game) in the game folder
Configure dgVoodoo control panel (application found in the archive)
Version 2.54: No specific configuration required
Version latest: For AMD cards with the latest drivers, it is required to set the Output API to Direct3D 12
Start GR where 32-bit Z-buffer can now be selected (meaning you don't have to force it in the options.xml file)
DSOAL is an open source libary that enables EAX, even without owning a soundblaster card.
Get DSOAL; latest version: http://vaporeon.io/hosted/dsoal-builds/
Extract the archive
Place the 3 files in the game folder.
Have fun. Maybe this should be made a sticky topic.