#the only exception I can think of atm is toruk which is indeed very literally ''last-shadow''

[nattikay]

Name translation doesn’t usually work that way, hence why regardless of what it means in its original language, we in English still call Jake “Jake” and not “Heelgrabber”. Moreover, as far as we know none of the canon Na’vi names really have “meanings” anyways; they're just nice-sounding collections of syllables.

The phrase “heel-grabber” would translate to something like tsunä niäyu, but it would be very strange to use that as a name.

If Jake were to get a truly na'vi name, not just a transliteration of his English name, what would you translate it as? Would it be a lì'fya translation of 'Jacob' or would it be a whole new name or would it be something else?

I'm not entirely sure what you mean. To do something other than a transliteration of his English name would just be to give him a brand-new entirely separate name, which I don't really feel is necessary.

The canon Na'vi transliteration for Jake is Tsyeyk (J is a very tricky sound to emulate in Na'vi phonology). "Jacob" could hypothetically be Tsyeykop or Tsyeykap.

We wouldn't be able to know his full name in the Na'vi format without knowing his father's first name, which we of course have no info on. For now as far as we can get would be:

Tsyeyk te Suli [father's name]'itan

I don't think he actually goes by that though; as far as we can tell he's still just known as Jake Sully/Tsyeyk Suli.

Interestingly, when Tonowari greets Neytiri by her full name he still addresses her as Tskaha, not Suli, which implies to me that Na'vi probably keep whatever family name they are born with throughout their whole lives regardless of marital status. I assume this happens to apply to name formats too, thus Jake keeping his human format despite otherwise fully integrating into Na'vi culture.