To put a nice bow on this topic, I will generalize what has been mentioned and are worth replicating.
Prerequsisite: the game must be in arm64-v8 for the offsets mentioned to work. You can get this version via apk pure.
You can effectively buy any item off the nopaew emporium since the variable holding the trade amount can be searched easily, and when you go to the memory chunk of this value, the 8th value above it contains the item's ID.
Since we can get the ID, this allows for reverse engineering of items that are not usually found in the emporium. So far, it has been found that class change tomes all follow the text literal job_rank_item. $class_name$. $class_name$ is a placeholder text that ought to be replaced by an existing class name. For instance, to find the class tome for Mariel's Hierophant class, the text you will search for is job_rank_item.hierophant. To get the associated starchart, simply add zodiac_ before the class name, like job_rank_item.zodiac_hierophant.
In GameGuardian, the names can be searched by prefixing the text with a : (colon-colon). So, you will search for :job_rank_item.hierophant. Afterwards, there tends to be a lot of result, so we will refine our search by searching for :. (colon-colon, dot). This is refining for the period that appears in our string literal.
After getting the returned values, we Go To the addresses of all the values individually. In my case, there are usually return values of 8~9, with the 9th value being from the emporium. My search of interest is usually the 5th out of 8 values, and the 5th value beneath it tends to be the ID of the item. My game is in Ldplayer, so it's possible different phones will have a different offset.
Apparently, skip tickets have a name of dungeon_ticket.skip.
Moreover, it has been found that the ID values have an interval of 160 between each other. This means that if an item within the Tome category has an ID of 1320, the next item will necessarily have an ID of 1320+160(1), whereas its previous item will be in 1320+160(-1), and the item itself can be calculated via 1320+160(0).
Such is the relationship of scrolls and keys, which can be written as:
High scroll + 160(-2) = low scroll
High scroll + 160(-1) = medium scroll
High scroll + 160(0) = high scroll
Green keys+160(0) = green keys
Green keys+160(2) = red keys
Green keys+160(4) = white keys
Green keys+160(6) = bold keys
Green keys+160(7) = skip keys
Keys and scrolls are in different categories, so you have to find the values for them as a starting point.
It is possible to have gaps in the interval, as you can see with the keys, so if you buy an item whose ID is in those gaps, the game will either crash or nothing apparent happens to your account. So, it is best to verify an ID to see if it corresponds to any item of interest.
Lastly, Guiding light and luring shadow items come after Fated star fragment's ID. So its values can be inferred as:
Fated+160(1), Fated+160(2), ..., Fated+160(16).
