I really don’t like the whole “Leia always knew”. She clearly didn’t, not even in TFA.
Again, they tried to mimic Return of the Jedi and the Ben-Luke dialogue. But back then Obi Wan and Yoda knew who Luke and Leia were because they were present during their birth, not because “the Force told them”.
How could Leia know that Rey is related to Palpatine? Luke can because he’s a Force ghost (maybe he has a greater understanding in this state), but personally I hated that scene and revelation that totally comes out of nowhere.
To me it’s better to have Luke just say “Because you’re a Palpatine” and then make him sit next to Rey.