How do translations work?
This is my first post here, so... hello, everyone!
I've been trying to setup a website where users can create H5P content and make it available for others. The website is geared towards Brazil, so it must offer Brazilian Portuguese text. I'm using H5P as a plugin of Wordpress 5.2.2, running on Ubuntu 18.04. So far, I have been able to get pt_BR text in Wordpress itself, and in the H5P Hub UI (except for library descriptions). In the H5P Editor, however, for some libraries, labels for input fields are all shown in Portuguese, while for others the "Title" input field label is in Portuguese, while all other labels are in English. You can see some correct output here and incorrect output here.
From what I understand, the H5P Editor bases these input field labels off each library's semantics.json file, or, if the display language isn't English, from "subsets" of it implemented in files in the library's language directory. However, in those cases where "Title" is in Portuguese and other labels are in English, there is a pt_BR.json file. Upon comparison with a language that is being correctly displayed, the pt_BR file seems structurally equivalent to the working language's (e.g., ja.json) file.
Unable to pinpoint a cause for this problem, I also couldn't tell in which repository to create an issue for it. Since I'm running H5P on Wordpress, and given that Wordpress is responsible for informing H5P of the selected display language, I decided to open an issue on the Wordpress plugin repository. I still remain unsure, though, if the problem really is there, in the libraries themselves, or somewhere in the H5P core.
I ask, then: how does H5P take translations and output it into, say, the H5P Editor? I've tried looking into some PHP and JS files, but neither of these languages is my forte, and the code seems abstracted enough that I can't quite tell what "path" the data from translation files takes from being opened to being output in the HTML page. Also, were I to simply try and change the English text to Portuguese in the original source... what would that source be? How would I set that change into effect? On my search on how to solve this problem I've read about having to change version numbers to put changes in effect, but I'm not sure if that's necessary in my particular case or not.
Any answers or pointers to documentation I may have missed are greatly appreciated!