Honestly I thought the game used some Naruto meta guides with that info...I mean Japan does like cashing in selling random data to fans.

While hinata&neji's element does seem to come out of nowhere, that does not mean they can't have different elements. I mean they are just cousins, whereas sasuke and itachi are brothers and yet one is lightning the other is fire. Blood relation does not mean exact same element.

At the same time, Earth is on neji's profile on the wiki while lightning on hinatas while neji do not have lightning and hinata does not have earth. Both are associated with more than one element, so I'm not sure how it is selected out of the "pool".

I do agree on the danzo one. He C*e fire, but he is mostly wind. i wonder if it's because his sharigan is quite prominently featured and the fact that most uchihas are fire?

Some blood-lines do have granted type of elemental use, as well as rumored fabled quirks to back it up. Such as Uchiha who're known to be heavily gifted with fire nature and most if not all Uchiha are born with fire nature. Beyond learning other elements are their own - aka Itachi learning Water style and Sasuke learning Lightning.

Hyuuga have small bits been hinted to have elements tied to Water, since their arts are tied to more of the medical side of things. There's a technique called water needle that involves a Hyuuga needed to perform the technique. But uh, yeah. Don't want to get too deep into it. I know this is a game, just thought some of these elements seemed weird.

According to wiki, Hinata is fire&lightning while neji is fire, earth and water.

Water needle is anime only, so depending on who you ask, might not be considered canon.

And as far as medical jutsu goes, hyuga clan's "gift" can be best compared to a microscope/magnifying glass that a surgeon have. Whereas water element is the scalpel etc tools that are used to perform medical procedure. So given two characters who are both equal water users, a hyuga would have an advantage. However, that doesn't mean every, or even most hyuga is a surgeon, that's backward logic--lots of people have microscope and are not surgeons. While given a choice, they might choose to learn water over other elements since they do have that advantage. But like you said, element is often associated with blood-line and is something people are, at least in part, born with. So it is perfectly possible that most hyuga cannot take advantage of their... advantage in medical jutsu because they don't have the more essential part of the gift.
Of course, eugenics could be a consideration, that is to say purposely marrying clan members to water users in hope of having a byakugan wielding water element child that's a perfect medical ninja. But there does not appears to be any hint at this particular eugenics practice being done.

It is true, however, that most hyuga is not associated with elemental release. Thou as the game have to give every ninja an element, they might get assigned to whatever they might be closer to. And in this case, for hyugas that does NOT have an elemental release, perhaps they would be assigned water or earth (earth due to its tie to taijutsu styles)

But like I said earlier, neji and hinata DOES have nature releases, so their element would come from that.

i can agree that most are confusing and that danzo being fire is absurd because he is wind, however most other ninjas are given them from a gameplay mechanic perspective as well as data book information, theres also a common theme that you can define a perosns element type based on there personal attributes and personality

Well - uh, you might've overlooked what I meant, or maybe I didn't explain enough. Sorry. So, Hyuuga in lore were spoken to be nomads who used their Doujutsu for medical purposes. That's what I meant as some Hyuuga branching into the medical field. That being said, not all Hyuuga go into this - yes. It was a long and forgotten age when they used their Doujutsu for medical arts, which was my example. A clear image of this would be Hinata where, in some sources of canon and anime dabbled a little in medical things such as pharmacy and herbs, where as the clan overseer wanted her to focus more into the combat aspect.

I won't lie when I say I haven't looked into the wiki for a while, so the elements for the Hyuuga are a bit distant to me. I never knew Neji had elements around those natures, let alone two. I know clans that have their own Hiden don't focus on elements - however people like Shikamaru have very brief instances where he performs Doton techniques for the sake of a strategy.

Or maybe I've drifted too far from the Naruto lore as a whole. Ahhhh.

I've noticed that thus far medical-themed ninja outside of Shizune have their elements tagged as water. When I say medical themed, I mean those who're known for their primary field being medical ninja. Which counts out other ninjas who just so happen to have healing as a skill aswell; Jigokudo, Mabui, Cee, ect.

in regards to this, this brings into question the actual viability of the healing tips ability, it might be incorrectly understanding, but a 40% increase in ninjutsu also increases healing by 40%, so if you are running a healing team with water ninjas, couldnt it possibly be better to run the water buff for the extra damage to try end it sooner instead of the healing only being a temporary buff? not really related to elemental status chocies themselves

now to me theres actually quite a few i would question outside of danzo who has all releases but predominately uses wind for combat because its his natural followed a bit further behidn by fire, i suppose to avoid clashes with onoki by having a wind fire barrier to fire lightnign for game mechanics... i get it but i dont really like it...

i dont know hinatas lightning premise but shes listed as fire and lightning in the data book, neji himself has 3 release types being earth fire and water i believe, i think both him and hinata have the largest affinity to fire though

now some others id question for example are tendo pain whos body yahiko has 0 affinity what so ever for lightning ninjutsus, he should really just be a water release ninja, because you dont magically change elements because somebdoy shoved some black rods in ya body

chiyo who id peg as a wind ninja especailly due to the wind symbols on all her scrolls and her placement as a sand ninja, the only major wind style using zone

i think shikamarus main release is supposed to be fire... but hes earth cause balacning i assume..

i definately question choji is the son of his father, both of which should be the same catergory, especially since choji has very little fire affinity

gai being fire release predominately but can ya say bout it..

this isnt going over everyone, but these are some examples of how the data book lists them

For the most part I can understand Onoki, since his KKG is a mixture of 3 elements into one. A very - very rare KKG that seems far too busted in the Naruto realm. Overlooking that, the things in regards to the Water comment does see a bit off. Idk, atleast for me it should make sense for the buff to be used for just that as opposed to the healing. Maybe it's because Azure is just mostly known as that 'Healing Main' as compared to anyone else.

People who use Hiden such as Yamanaka, Akimichi, Aburame, and Nara use either Ying or Yang release, an influence of chakra that benefits whatever their family technique revolves around. That being said, anyone in the Naruto universe can learn other elements. As stated by Yamato saying that a Jounin can learn up to 2-3 elements at a time. I think it's a requirement. Idk.

in regards to it, every user has a nature affinity and some can have ying and yang affinitys as well, and they existed before kakashi gave the paper explaination, i dont think he incldued them as the paper test can only help define elements, but the data books list there elemental order for the most part, and the ones i listed were the top affinitys, many have more then one, danzo himself having them all + ying and yang, you can find msot of these on the wiki pages to since hte databooks arent fully translated