Short answer: Probably not.
Long answer: Probably not, and that's due to the folder names that ffxi gives to each of your characters. Currently, the folder that represents Seteyu's macro's/settings on my machine is called "bec678". Why? I have no idea, but I'd bet its stupid programming on SE's part. I don't know if I install FFXI on a new machine, or even if I activated my POL account on another POL/FFXI installed machine, that the folder then would still be called "bec678" on that new machine. For that reason I said what I said in my first reply was because I assumed the worst possible case, and gave the method that would work regardless of setup.
However, I'm betting you are just trying to do a straight swap, FFXI on a new machine, you want your macro's transfered. In that case, do this instead. Just copy the USER folder onto your flash key. Walk over to the new machine. Make sure you've all characters/accounts activated on the new box (very important). Open up the USER folder on the flash key, drag the window to the upper left of your screen. Then go find the local USER folder on the new box. Open it up, and drag it to the lower right part of the screen. Compare folder names. If all the names match, just overwrite the local USER with the flash key's version. If some match, but not all, overwrite the same-named local folders with the flash key version. If none match, well I can explain how to figure that out, but it means another wall-o text. This method is a little more risky than my first one however.
Man, explaining what I just..know without sounding like an ass or making a huge ass wall of text is hard.