https://bugs.winehq.org/show_bug.cgi?id=51105
--- Comment #6 from Conor McCarthy cmccarthy@codeweavers.com --- (In reply to Constantine from comment #5)
However, most important thing is that game uses it's own d3d12.dll now. It is located in the selected for installation folder.
For me, it was not enough to change drive_c/windows/system32/d3d12.dll It was not used. Game used this one: drive_c/Program Files (x86)/Diablo II Resurrected/d3d12.dll
Is your Wine prefix set to Windows 7 (using winecfg)? AFAIK the d3d12.dll shipped with the game is only for D3D12On7 and it would make sense if the game uses it when the reported Windows version is 7. The DLL was not used when I tested in a Win 10 prefix.