GREENandYELLOW
2x...and defending
I think there is a lot of differences.
GGG - better footwork, more pure offensive style, more technically gifted, ability to throw any punch and do so with power, so far better chin
Kovalev - better outside boxer, better one punch power, in a better division and thus probably has faced a little better competition
Their styles are different. Kovalev has shown to box more and not always be a pressure offensive fighter, GGG is a offensive stalker. Kovalev's defense can be broken because he isn't always able to retreat quickly or have head movement, whereas GGG defense is usually penetrated because he is always coming forward. Both have great power but do it in different ways. I think GGG throws a larger variety of punches and has power in every punch. Kovalev throws a more traditional punch repertoire and has greater single punch power. Kovalev's division is stronger and therefore I think he has faced slightly better competition. GGG has looked to have a better chin so far, although Kovalev has faced bigger punchers and has been hurt, but not in serious trouble.
GGG - better footwork, more pure offensive style, more technically gifted, ability to throw any punch and do so with power, so far better chin
Kovalev - better outside boxer, better one punch power, in a better division and thus probably has faced a little better competition
Their styles are different. Kovalev has shown to box more and not always be a pressure offensive fighter, GGG is a offensive stalker. Kovalev's defense can be broken because he isn't always able to retreat quickly or have head movement, whereas GGG defense is usually penetrated because he is always coming forward. Both have great power but do it in different ways. I think GGG throws a larger variety of punches and has power in every punch. Kovalev throws a more traditional punch repertoire and has greater single punch power. Kovalev's division is stronger and therefore I think he has faced slightly better competition. GGG has looked to have a better chin so far, although Kovalev has faced bigger punchers and has been hurt, but not in serious trouble.

) and bring gifs into this 
. If you want to discuss overall footwork in a Floyd Mayweather/Andre Ward style then absolutely...GGG isn't on that level as far as offensive/defensive transition, positioning himself at a distance. But when it comes to offensive punch setup, stalking an opponent, and cutting off the ring, GGG is one of the best in boxing currently.
GGG hasn't got hit with the shots kkkov has? who is the hardest puncher he's faced Stevens? who was a hard puncher at 154? 
never heard that one before 
This is also why I said it's hard to gauge GGG since we don't know his true ceiling. He hasn't fought anybody on the level of Pascal/Hopkins. 
