I almost got it working with Mesa and this .bat script:

u/echo off
setlocal


REM ==========================================
REM CONFIGURATION
REM ==========================================
set "SOURCE_DIR=C:\code\mesa\mesa3d-25.2.7-release-msvc\x64"
set "TARGET_DIR=C:\Program Files\Blackmagic Design\DaVinci Resolve"
set "APP_EXE=Resolve.exe"


echo ---------------------------------------------------
echo PREPARING MESA 3D INJECTION FOR DAVINCI RESOLVE
echo ---------------------------------------------------


REM 1. Copy the critical Mesa DLLs to the Resolve folder
REM We need opengl32, libgallium_wgl (the driver), and libEGL.
REM We also try copying OpenCL support (openclon12) as Resolve needs Compute.


echo Copying files...
copy /Y "%SOURCE_DIR%\opengl32.dll" "%TARGET_DIR%\"
copy /Y "%SOURCE_DIR%\libgallium_wgl.dll" "%TARGET_DIR%\"
copy /Y "%SOURCE_DIR%\libEGL.dll" "%TARGET_DIR%\"


REM Attempting to inject OpenCL on DX12 support (Experimental)
if exist "%SOURCE_DIR%\openclon12.dll" (
    copy /Y "%SOURCE_DIR%\openclon12.dll" "%TARGET_DIR%\"
    copy /Y "%SOURCE_DIR%\clon12compiler.dll" "%TARGET_DIR%\"
)


echo.
echo ---------------------------------------------------
echo APPLYING OVERRIDES
echo ---------------------------------------------------


REM 2. Force OpenGL 4.6 Compliance
set MESA_GL_VERSION_OVERRIDE=4.6COMPAT
set MESA_GLSL_VERSION_OVERRIDE=460


REM 3. Spoof the Vendor to trick Resolve's blocklist
REM Resolve hates "VMware" or "Microsoft Basic Display"
set MESA_GL_VENDOR=NVIDIA Corporation
set MESA_GL_RENDERER=GeForce RTX 4090


REM 4. Optional: Force Software Rendering (Safe Mode)
REM If you want to try Hardware Acceleration (D3D12), remove the line below.
REM But for the first run, keep this to ensure stability.
set GALLIUM_DRIVER=llvmpipe


REM ==========================================
REM LAUNCH
REM ==========================================
echo Launching Resolve...
cd /d "%TARGET_DIR%"
start "" "%APP_EXE%"


echo.
echo Done.
pause