HIHI!! omfg you're right a master doc would be a good idea huh... i've just been rambling to myself up until this point, i didn't expect the sudden attention haha. YOUR MIND IS HUGE. lemme try to organize my thoughts for once

i like the idea of brogy and dorry speaking a more "archaic" form of elfram! and by "archaic" i mean, like, the way your great(x3)-grandparents spoke or something. since giants live upwards of 300 years, it would make sense if their perception of time and age differed from that of humans. language change is also pretty slow in the grand scheme of things, so one hundred years isn't all that long lol

i think when they lived on the moon in the city of birka, the ancestors of shandians, skypieans, and birkans all spoke the same language. then, after moving seaside, they gradually branched off into their own distinct varieties (internal linguistic change is bound to happen regardless of external conditions as speakers are inherently innovative). so they would share the same proto-language, i suppose. and since it was a MOON LANGUAGE, it probably sounded crazy different from seaside ones. though i imagine contact (however minimal) with other islands in paradise led to some borrowing (and nativization in certain cases). enel destroying birka is insane in this sense actually cuz it's like congratulations idiot your native language is endangered now (not extinct mind you, i doubt every speaker of birkan still lived on the island). skypiean and shandian... hm... there's definitely been skypiean influence on shandian over the centuries; like arabic with spanish and farsi and indonesian, or english with... um, a lot of languages. a large if not key aspect of colonialism is the systematic and social suppression or erasure of indigenous languages (and the imposition of a settler one), so there's obviously gonna be severe linguistic consequences. hm.... you've given me a lot to think about! i might elaborate more on this later. thanks for the ask! i appreciate it.