Pro/ENGINEER is long discontinued and replaced by newer Creo Elements/Pro software, nevertheless the conversion of .sec (Sketch) to .dxf (2D CAD) format was perhaps possible in the original software.
As far as we know, no 3rd party software can handle this type of .sec files, so the original program remains the only viable choice for sec to dxf conversion.
Updated: May 14, 2020
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