Ever since Final Fantasy VII Remake came out, fans were expecting lots of story changes to the Final Fantasy VII Rebirth.
Compared to the OF FFVII, Remake and Rebirth have changed the order of story beats to make it more linear unlike the OG’s non-linearity.
Remake and Remaster adds the presence of Whispers, new spirit-like beings who attack anyone going against their destiny.
One of the biggest changes is seeing Zack as a playable character, who was supposed to have died before the game starts (In FFVII: Crisis Core).
Due to Aerith’s connection to the planet in a genetic way, it’s implied that she knows the future... and her tragic ending as well.