FreeCAD supports the STL format (Streolithography for 3D printers) and can import it and further save in FreeCAD's own .fscstd drawings. This works best with STL models that contain single entity and files that contain 3D data split to several parts may not be imported properly.
Convert Stereolithography CAD file to FreeCAD drawing.
We found one software available in the database for this conversion.
Multiplatform software - convert stl to fcstd on any platform
An open source multiplatform 3D CAD/MCAD/CAx/CAE/PLM modeler
Convert from stl file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.