er...your friend is wrong. OoT and MM's Link are the same, but TP's is a whole different person. TP takes place possibly 100's of years after OoT, so unless Link can live that long...it's impossible.

The Link from WW and PH are the same as well, but the one from MC is a completely different one.

The Oracles and LA? Not 100% sure, but I do think the one from LA is the same from ALttP, not the Oracles