Now it started to get a little difficult to choose...
I go with Pocahontas now. Sure, she's very connected to nature, and probably would have no problem figuring out that Te Ka was Te Fiti. However, she is too introspective and waits a lot for spiritual guidance before she acts (if she acts at all). Moana relied in the ocean once or twice, but she knew exactly when was the right time to act. I can see Poca waiting for the ocean to tell her what to do just like she waited for the wind, and I don't see the ocean giving Moana all the answers she needed.

My other choices would be Anna or Rapunzel. I mean, they did fine in their little "first time ever" journeys, but Moana's required a physical prepare and a sense of adventure that they lacked. Ariel and Anna would be a little too impulsive, but that would be a smaller problem than Pocahontas waiting forever to decide to face Ka Ka Moa or Tatamoa.

This is getting hard! I do think the winner should be either Pocahontas or Mulan. I guess Anna because she just isn't as physically capable as the others.

She's definitely brave, but she is probably one of the not as smart final candidates here which could get into some trouble for her.

Same as before. She'd die on the ocean.

Same as before.
I think Anna might do well. She's passionate and determined enough to reach Te Ka, and since she has a heart of gold, I bet she'd realize Te Ka's true identity and restore her heart.

I see her perseverance. But she doesn't have the clever instinct of the others.