Thank you Kouen ;)
sorry to be bring this up after such a long time, the truth is i thought i had it all figured out and i did like you said kouen. But i didn't test it yet :( now that i have i still see all the effects. I have a .pk3 file now in one of my mod folders named forcepowers.pk3 , in it are all the .efx files who are blank. So in theory when i start the mod the force powers should become invisible? sadly it is not the case.
Any other way of letting the effects disappear? I tried putting a pk3 file with blank efx files in the base folder too, didn't work :(