Sure, but it requires a lot of patience. You still need the .bat file to tell you what to copy. There are lots of files in quite a few locations so there's no easy way to do it. Guess it would be easier to go to a friend with a PC, install M2TW, install the mod, run the campaign setup, copy the mod's folder on a stick and then copy it back on your Mac.
However, if you really-really want you should do it like this:
-open the .bat file
-look for the campaign you want; make a note of the letter/number it uses;
-look for the logical test ("IF /I '%Choice%'==...") and make a note of the label ("Item_") associated with that letter;
-scroll to the corresponding label (e.g. :Item1) and start copying manually whatever the batch commands in that section tell you to:
so xcopy %MTW%\menu\menu_970 %MTW%\menu translates to
open a source window to \mods\conquest\data\menu\menu_970
open a destination window to \mods\conquest\data\menu
copy all files from source to destination, overwriting when asked
repeat until done; be sure not to skip lines and to stop when you reach the GOTO Start command
now pay attention that each %MTW_% variable points to a specific folder and you'll have to translate that in a path to a subfolder; the list is in the file, under the long ECHO section at the beginning; so, if %MTW% was \mods\conquest\data, further down you'll find %MTW3% which is mods\conquest\data\menu\symbols to which you have to append some subfolders so xcopy %MTW3%\fe_buttons_24_970 %MTW3%\fe_buttons_24 means copy all files from mods\conquest\data\menu\symbols\fe_buttons_24_970 to mods\conquest\data\menu\symbols\fe_buttons_24_970;
Having fun yet?
Now, assuming you really are determined to do all that, it might be a moment to stop, take a breath and think before you act. Might be a good idea to do this not in the M2TW folder itself but in a separate folder, say, on your desktop, that you can name, say, "970 Campaign" in which you create the whole structure of subfolders (\mods\conquest\data\_whatever_) so you can later copy all its contents at once in your M2TW folder and, maybe, ask uanime5 for permission to post download links to what would be "pre-made campaign folders" that other friends of yours, that thought it makes more sense to buy a Mac and not a PC, might use for themselves. Because later you'll want to play the 1220 Campaign, then revert to 970 again, then try something else and wouldn't it be great to do all that tedious work just once?
Anyway, I'm pretty sure that Apple has some system of batch commands of his own so might be even a better idea to learn that and translate the Windows .bat into whatever a Mac can read and execute.