I’m not too worried about changing the occasional word spoken on-screen, but it does help if the mouth movements are similar.
Speaking of that, I’ve been thinking a bit more about the small scene of Finn, Poe, and D-O. For an edit where Rey Palpatine is a lie, this dialogue needs to be cut or changed in some way. The first inclination I had was to change the dialogue to establish that Lando’s daughter was the target of Ochi, to somehow lure Luke to the Emperor, but this is sort of unconnected from the rest of the plot and doesn’t make much sense at this point in the story.
So then I thought that there is one other reason why Lando would be involved with Luke chasing Ochi across the galaxy, and that was if it had something to do with Luke’s saber. This would complete the whole ‘story for another time’ moment in TFA while also being relevant to Finn because he was there when that story was originally teased.
“This droid has a ton of information about Exegol”
“Wait, coneface?”
“D-O”
“Sorry, D-O”
“He was going to Bespin with Ochi of Bestoon.”
“Why was Ochi going there?”
“To bring a lightsaber he was supposed to take from Cloud City, to the Emperor.”
Changing ‘Exegol’ to ‘Bespin’ would be fairly simple because his line would only need to be shifted slightly forward to be masked by the previous shot, and ‘lightsaber’ is very similar to ‘little girl’ in terms of syllables and mouth movements. From ‘Cloud City’ onward, this change could be covered by cutting to Poe’s reaction shot.
This change also fixes something weird about the original scene, which was that Poe’s confused reaction of ‘Why was Ochi going there?’ doesn’t make sense because everything they know about Ochi points to him frequenting Exegol. That Ochi was going to Bespin allows Poe’s confused reaction to make sense.
Finally, making this scene about Anakin’s lightsaber ties into the following scene, where Rey attempts to destroy the saber in anger and fear. This connection between scenes could be made even stronger if we extended Luke’s dialogue with a reaction shot of Rey, and perhaps shifting her line up to make all of this work. There is a good candidate of her looking at the burning ship from earlier in the scene, and over this reaction we can have Luke continue his admonition:
(Luke catches the saber)
“Master Skywalker!”
“A Jedi’s weapon deserves more respect. The Emperor sought to destroy it…so what are you doing here?”
Now Luke’s statement doesn’t come out of nowhere, since it bridges the previous scene and explains why the Emperor was after Luke’s saber - he clearly feared it for some reason. Perhaps he foresaw that it would be used in his annihilation, or simply that it featured in his future somehow. But the irony of this is that Luke is tying Rey’s action with that of Palpatine in wanting to destroy the saber, further linking the two. Also interesting is that Palpatine seeking the saber led to intelligence about Exegol falling into the hands of his enemies, resulting in his ruin.
One final bonus of this change is that if we set up that the Emperor now fears Luke’s saber, it becomes less random that this is a weapon used in his destruction.