When Kirito logs in to ALO with his SAO account, all his SAO skills and points and even Yui's heart are loaded; so we can conclude that the same thing must have happened to his avatar, too. If so, why didn't Sugu recognize him and if not, why is that?
When people were trapped in SAO, their avatars became exactly similar to their real-life bodies, so recognizing someone from real life was possible there.
Kirito at SAO:
Kirito in real life:
But in ALO, it's totally different.
See Sugu and leafa as an example:
Kirito's avatar in ALO may resemble his character from SAO, yet it's still different. A player with that avatar could look totally different in real life. And people that play MMORPG's are not use to talk about their real life at the game.
So, Leafa didn't recognize Kirito because there was no reason for her to do so in a game like ALO.
When Kirito went onto ALO it said that his apearence will be randomised, however, since all of his data was transferred from SAO he looked the same as he did in SAO which was exactly how he looks in real life but when Sugu saw him she would not have thought it was her cousin because all the looks had been randomised.
Suguha didn't resemble her true self because it was a different machine in the anime but by the same creators... remember how they "asked them to touch themselves all over so they resemble the same?" Remember how there were mirrors and when they looked inside of them they looked exactly the same as what they look like in the real world? Maybe that's why. One, because f it's a different machine, then they might've forgot to make it so you had to touch yourself all over, two, because they didn't receive any mirrors in Alfheim.