Yes, with the caveat that you'll need to open up the doom_complete.pk3 file WadSmoosh generates, and delete the file "menudef.txt" there to fix the startup error. Zandronum doesn't support some of the menu scripting features GZDoom has.
https://zandronum.com/tracker/view.php?id=3205 <- This is the issue that causes the menudef error, so when Zandronum 3.1 finally comes out, you shouldn't need to do the hack described above.
The doom_complete.pk3 file is actually just a ZIP file with a different extension (suffix), and you can open it using whatever you normally use to inspect and edit the contents of ZIP files. Just inside it, you'll find a file called MENUDEF.TXT. Simply delete it, then try launching in Zandronum again.