but some Pro NaruHina fans says that Naruto give Hinata a hint on the "look in the person eye speech" and also use Neji, Kiba, & Shino expression at that moment.
Why worry about what NaruHina shippers think? Of course they're going to say stuff that supports their viewpoint. But it smacks of desperation to view the scene in 559 as proof of NaruHina, and here's why.
Transcript from 559:
Neji, Kiba, and other-nin: (arguing about the sudden appearance of Naruto's clone)
Neji: Are you really Naruto? You're not another one of those white things, are you?
Naruto: I'm Naruto!!
Neji: How do you plan on proving that?
Hinata: It's Naruto-kun. Just look at his eyes, you can tell. Besides that, he came to our rescue...
Shino and Kiba: ...
Hinata: Sorry, Naruto-kun...everyone's so suspicious of you...
Naruto: Now that I'm here, we don't have to just sit on the defense any longer!! I'll start from one side and find all the fakes!! Let's all go together!!
Hinata: (internal whinging about how she's crap at everything and no good)
Naruto: Don't worry about it, Hinata...I'm pretty lame anyway, considering you've already had to save me at least twice now!
Hinata: I...I wasn't...worrying about that...
Naruto: It's all in your eyes. Don't get so down on yourself! You're strong!!
Hinata, Shino, and Kiba: ...
Logical interpretation:
+ Hinata defends Naruto's clone, telling the guys they just need to look into his eyes for proof.
+ The guys are unconvinced.
+ Naruto offers a plan and boosts morale with a pep talk.
+ Hinata has no confidence, as usual.
+ Naruto realizes Hinata needs an additional morale boost and more pep talk, resorting to self-deprecation and a rehash of her accomplishments to try to make her feel better.
+ Hinata denies feeling weak.
+ Naruto defends Hinata from herself, using her own words as a reminder that looking into someone's eyes is proof of their character.
+ The guys are unconvinced.
Naruto mentions what he can see in Hinata's eyes because she told Kiba, Shino, and Neji to look at his eyes. It was about establishing identity, about trusting each other to fight together. That's it.
So according to the NaruHina shippers you mention, Naruto was giving Hinata a hint about what? That he loves her? That he's thrilled she's in love with him? Pfft.

This is what Naruto looks like when the girl he loves says she loves him. No hinting about the nature of feelings is required. It's right there on his face.

This is a guy giving a sad, unconfident girl a pep talk in the middle of battle.