So I have FFXED and I think now that I have replayed the FFX story I want to start from scratch with the "Expert" sphere grid. Now I was looking over the expert sphere grid and saw a few unfamiliar abilities. Sure enough I used to Final Fantasy Wiki and found out that they are unique to the international version of FFX. Now I am using the NTSC U version of FFX. Would enabling the expert sphere grid and unlocking these abilities make them use able on my US version of FFX or would the ability just not do anything?

AFAIK, those abilities weren't coded in any version but the international version.
I guess either your savegame will crash, either it won't produce any effect.

Yah, makes sense. Just didn't hurt to ask.