As mentioned above, FFXIV in particular is a team effort of the sort that’s incredibly rare in Japanese games localization, so it would be hard to really put a number to the people involved in this aspect of the project. We translators are very fortunate to have an ongoing dialogue with the devs regarding the lore, UI, cutscenes, and more. This allows us to spot potential localization pitfalls, but also helps us have a more sound understanding of what we’re translating, and allows the dev team to ask us questions in turn.
The main teams we end up working with directly here in Japan are the event team (responsible for lore and story), and the cutscene team. I work with the former frequently on lore and naming checks. This involves a lot of them sending me large files to comment on, and also more casual back-and-forths via messenger where we ask questions, discuss ideas, or lament the fact that there are so many fire attacks because we’re really running out of synonyms.
When it comes time to translate and record the voiced scenes for main scenario, representatives from each language usually meet with the writer in charge about how long it will take to act out the lines that need to be synchronized to animations, to see if we need to adjust the script or performance in order for all languages to take roughly the same amount of time.