eDrawing assembly files (.easm) cannot be typically converted to anything else, simply because they are used as previews and for printing - not for further editing. The exception to this are files exported with the option 'allow save' which apparently allow for some basic export to other formats, for example STL.
If you need the model exported to other 3D modeling / CAD format, such as AutoCAD DWG, you will need to obtain the original source from which the eDrawing file was exported in the first place. Otherwise, it is likely that you will be unable to convert easm to dwg directly.
Updated: March 14, 2017