>>56392385tl;dr is it's Hoenn replaced with only Gen 1 & 2 for wild encounters with access to and trainers with cross-gen evolutions, has day/night overworld including other shades such as sunset, has Gen 4 sprites, has an actually useful Pokedex so you don't have to look at a webpage outside of the game, and has updated battle mechanics up to Gen 9 including physical/special split without the VI+ battle gimmicks.
I haven't played Liquid Crystal but here's the pages
>liquid crystal page of info https://www.romhacking.net/hacks/1901/>johto edition page of info https://www.pokecommunity.com/threads/pokemon-emerald-johto-edition-version-1-1.527870/If anyone goes to play it make sure you patch the Trashman ROM. Not sure if some text bugs I've seen like the Repel prompt using the words Poke Ball are because I patched a non-Trashman one but then still used a save 1 hour into the game since I didn't want to start over.