Is it the Vader part of it that is a continuity error, or just how the scene itself played out?
I have issue with the entire scene. Why is the Tantive there? I know that the Story Team has said that the idea was that the General, Admiral, whatever, was supposed to escort Leia to Tatooine, but that makes little sense to me. You have a courier who is supposed to be delivering plans vital to the survival of the Rebellion in the belly of a ship during a huge battle? That makes no sense. Then, you have Vader, who says
Don't play games with me, Your Highness. You weren't on any mercy mission this time. Several transmissions were beamed to this ship by Rebel spies. I want to know what happened to the plans they sent you.
Well, they weren't beamed to THAT ship. They were beamed to the General's ship. Then the soldiers ran the plans to a door, that conveniently wouldn't open except for a small bit, which led to a slaughter. Its damned convenient and a plot contrivance for a cool moment.
I believe the scene would work better if someone from the film proper, why not Bodhi? Because I felt his character was just a plot device anyway, so why not finish it off? I think it would work better if Bodhi actually survived on the planet, and as opposed to getting it transmitted out because something happened, maybe the long distance transmitter gets destroyed and the only way out is to get it off planet. So Bodhi somehow gets the plans, and takes off in a shuttle with a few surviving rebels. Tarkin orders the destruction of Scarif; Krennic, Cassian and Jyn die. The rest of the fleet goes to hyperspace, but several ships including an Interdictor and Vader's destroyer come in. Bodhi can't escape. They're pulled in with a tractor beam. Bodhi is starting to try to transmit but he's having issues as the Imperials are blocking all signals. The rebels are getting ready for boarding, almost mirroring the scene at the beginning of ANH, but then the scene continues almost as in Rogue One, but instead as others are mowed down behind him, Bodhi manages to transmit the signal. A look of relief crosses his face just before we see a red blade cut through his chest. Vader pushes Bodhi's corpse aside and sees where the signal went to -- a ship on the edge of the system.
We cut to the Tantive IV where two droids, Artoo and Threepio are monitoring a station. Threepio tells an Ensign something is coming through. The Ensign burns the files to a disk and goes running to take it to Captain Antilles. Antilles then gives it to a figure in white asking her what it is. Princess Leia turns and responds with one word: "Hope."
That, in my opinion, acts as a far better bridge scene by keeping a character who you just spent two hours with (whose character would need to be expanded a bit to add more of an emotional impact to his death) dying as he saves the rebellion. It keeps intact the Vader moment. It keeps intact the continuity from ANH and it keeps the intent of the scene the same. I just think it works much better myself but I may be the only one.