STEP models can have colors and they import in FreeCAD 0.19.3 latest version and earlier - please see this thread:
https://forum.kicad.info/t/nightly-step-export-leaves-pcb-without-components-vrml-issue/32459/6?u=otoien
The only limitation I have experienced is that if transparency is defined like for LEDs it is lost on export from KiCad (might not be supported in STEP models).
Application: KiCad (64-bit)
Version: (6.0.0-rc1-404-gf2639e2928), release build
Libraries:
wxWidgets 3.1.5
libcurl/7.78.0-DEV Schannel zlib/1.2.11
Platform: Windows 10 (build 19042), 64-bit edition, 64 bit, Little endian, wxMSW
Build Info:
Date: Dec 12 2021 09:00:02
wxWidgets: 3.1.5 (wchar_t,wx containers)
Boost: 1.76.0
OCC: 7.5.0
Curl: 7.78.0-DEV
ngspice: 35
Compiler: Visual C++ 1929 without C++ ABI
Build settings:
KICAD_USE_OCC=ON
KICAD_SPICE=ON