Per this document https://learn.microsoft.com/en-us/windows/win32/direct3dhlsl/specifying-compiler-targets, it seems the effect framework start from d3d10 is marked as legacy , what is the equivalent in d3d12 (if any) ? many thanks!!!
The fx_* profiles are deprecated in the FXC compiler and the D3DCompiler_47.dll that's available for redistribution and included with the Windows 10 OS. They still work, although fx_5_0 is missing support for a few newer features from the latest Shader Model 5.0.
The runtime component is the Effects for Direct3D 11. The latest version is on GitHub, but is provided very much in an "as is" state. It's more or less unchanged for a few years so I marked the repo as 'archive'.
There is no Effects (FX) port for Direct3D 12, and the new Shader Model 6 DXIL compiler has no support for fx_* profiles.
See this blog post
Now as to why is a much longer story, but in the end most engines have their own materials/effects system, so it never got much use for DX10 or DX11.
If you are looking for a basic material/effects system to learn Direct3D then take a look at DirectX Tool Kit for DX11 or DX12.