It’s a vain exercise to try and measure and compare genius, but that hasn’t stopped this scientist from saying that einstein was a peerless genius and hawking was an ordinary genius.
I get why you can say Einstein is special amongst scientists for the work he did and the influence he has. And if anyone was a genius, it was Einstein. But to say he is more of a genius than someone else is folly.
In such a debate I am reminded of John von Neumann and his genius. If you asked the smartest people in the 20th century who had the most brilliant mind, they would point to him. Yet von Neumann fretted that “in the future he would be forgotten while Gödel would be remembered with Pythagoras.” He may have been a peerless genius to his contemporaries, but he felt he was not in the same league as Gödel (never mind Einstein).
In short, other than a fun drinking game, it is pointless to try and say who is more of a genius. There is nothing quantifiable about it.