obj to jt conversion is typically a matter of export 3D objects saved in OBJ format to JT Open CAD format, which is unfortunately not supported in every 3D modeling or CAD software.
Still many tools do support JT format directly, or enable it via 3rd party plugin, so it should not be hard to achieve this. But since OBJ format is a bit barebone, it might need a bit of tweaking before you can export it to JT format.
Updated: September 27, 2023