It probably would be, but what point is there having touhou in 1 ad? The countries added by the mod are mostly cast focused, and not only does most of touhou's cast just not exist that far back, there simply isn't much established gensokyan history for ET to play with. (Though technically Gensokyo shouldn't exist at all until 1885.)

well it'd be far too much effort to add a version for each start date but it'd be really funny to at least have basic compatibility even if it's the same starting gensokyo for all dates