You can export 3D model in ACIS format.
Just one problem:
First off, export a 3d model from within ACAD. as a ACIS file.
Load the file into Solidworks and try to identify the ACIS version number ACAD (secretly) uses. If you try to import a wrong version, ACAD just gives a dumb 'error reading file message'.
The .SAT file is text, so you can read the first few lines, and (maybe!) make a reasonable (hopeful) guess.
Once you know a version that works, when you go to save as a .sat file in solidworks, use the options at the file select screen to choose you .sat version. There are MANY versions, so choice becomes problematic.
Also .STEP files work, but you only end up with wire models in ACAD.
ACAD can't create a solid from wire model. Dumb as... doggy do!
Mastercam is good at importing one file type and exporting as another.
Solidworks can save in a reasonble number of formats, but ACAD is very limited. The ACAD help mentions, IGS files, but ACAD doesn't do anything with them. That's dumb?
ACAD has a few other orphan formats, that nothing else likes!!
I like ACAD, but hate the limited formats supported.
Maybe there are some lisp plugins available.
You can write stuff in lisp to do almost anything. (if you can ever master it!)