If you're wondering how to find Arylina's Diary in Nazjatar, the most important things to note are:
Here's a couple of screenshots of where I found mine – Arylina's Diary always looks the same, but it could be in one of the multiple locations within the quest area shown below:
Arylina in Nazjatar, one of the quest giver NPCs. Also spookily reminds me of those weird shadow children things in the very first Silent Hill game 😱
90's kids and retrogamers, if for some reason you don't want to sleep – or just want some corrupted nostalgia, here's the “Larval Stalker” from the classic Playstation horror-game.
So that's how you find the pesky teleporting diary in Nazjatar belonging to our transparent friend Arylina.