Who the best h2h combatant in avatarverse

From aang and korra story arc?

Ty Lee? :D

Amon

Amon, or maybe Zaheer

Probably Amon.

Ty Lee, Amon, Azula, Zaheer, Asami

Ty Lee very very easily. She just one shots people and is easily the most agile character short of Ming Hua and a couple of airbenders.
Suki comes second after she learned chi blocking.

If Amon knows chi-blocking:
Ty Lee>Amon>Suki
If he doesn't:
Ty Lee>Suki>Amon

TyLee and Suki>>Amon>Azula>>Zaheer=Korra. I want to put Asami in here but she has no feats without her glove.