Would be interesting actually. Giant Man is extremely strong (based on Endgame, his biggest form can apparently lift hundreds, if not thousands, of tons) and, unlike Hulk, also has the actual size and mass behind him, which helps a huge deal in this scenario. Because the Hulk didn't just have to deal with Fenris' brute power. He had to deal with the fact that Fenris was A LOT bigger and heavier than he was, which made things a lot more difficult.
Here are some size comparisons:
And then this, which is poor quality (though the best I could find at the moment), but it gets the scale across:
I wouldn't be surprised if this clip gets taken down soon though.