All of those others who have appeared in various TV shows claiming to be gods - Thor ('The Incredible Hulk'), Apollo ('Star Trek'), Aphrodite ('Hercules: The Legendary Journeys'), Krishna ('Xena: Warrior Princess'), and Sun Wukong the Monkey King ('Journey To The West') - were actually pan-dimensional beings with great powers who crossed over from their dimension to Earth Prime-Time. And each of them had counterparts in the other TV dimensions.
We learned that definitely when Hercules' pal Iolaus ended up in the "Evil Mirror Universe" where Ares was the God of Love.
So when the spirit of Isis possessed Lois Lane in that TV dimension that houses 'Smallville', she was not the same Isis who possessed Andrea Thomas (only when called upon) in the main Toobworld back in the 1970's. They were dimensional doppelgangers.