A note that we generally have to test the mod on both v1 and v2, as well as Switch and PC. I run v2/PC, Kody runs v2/Switch, and dqxdude runs v1/Switch
As we've progressed with working on the translation, it became increasingly apparent that v1 and v2 are pretty distinct. And, for the most part, the files we've translated maintained the same structure between both versions, but with additional entries for v2 stuff, so we've been able to just switch to using the v2 files for everything without issue...
That is, until NpcInfo. The structure of NpcInfo changed quite a bit so just running the v2 version of this DataTable will cause v1 of the game to crash (yay!).
Luckily, with v2, they eliminated the need for us to edit the DataTable directly, because now it references a new StringTable for the NPC names, so we can just edit that. The downside is that NPC names won't be translated if you're using v1 unless you're using an optional patch (that contains the edited v1 NpcInfo).
Tl,dr: It's easy to think of v2 as just a "DLC" or "Expansion", because that is how it is marketed. But we almost have to treat it as a different "updated" version of the game.