According to Unity's Shader compilation documentation under "Different shader compilers": https://docs.unity3d.com/6000.1/Documentation/Manual/shader-compilation.html

Different platforms use different shader compilers for compilation as follows:

• Platforms that use DirectX use Microsoft’s FXC HLSL compiler.
• Platforms that use OpenGL (Core & ES) use Microsoft’s FXC HLSL compiler, followed by bytecode translation into GLSL using HLSLcc.
• Platforms that use Metal use Microsoft’s FXC HLSL compiler, followed by bytecode translation into Metal, using HLSLcc.
• Platforms that use Vulkan use Microsoft’s FXC HLSL compiler, followed by bytecode translation into SPIR-V, using HLSLcc.
• Other platforms, such as console platforms, use their respective compilers.
• Surface Shaders use HLSL and MojoShader for code generation analysis step.

Based on the description, shaders always get compiled via the Microsoft’s FXC HLSL compiler (DirectX) and if the target is not DirectX get further translated via HLSLcc (e.g. OpenGL, Vulkan), so may it be possible to translate games with DirectX shaders via HLSLcc to OpenGL or Vulkan? 🤔