Chewie: In the novel, he seems to recognize Obi-wan. In the films, he never meets Anakin and Obi-wan, just Yoda, and never sees him again.
While, it may be true Chewbacca met Yoda and Ahsoka, there is no indication that he met Anakin. Even if Chewbacca has met Anakin, Chewbacca would have assume Anakin was one of those Jedi killed in Order 66.
That's right, Chewbacca and Obi-Wan have a history together, as they fought side by side in this conflict. In fact, with Obi-Wan's help, Chewbacca successfully colonized Alaris Prime and turned it into an economically prosperous stronghold for the Wookiees beyond their home planet of Kashyyyk.
He hailed from the planet Kashyyyk and became a Wookiee military leader. During the Clone Wars, he was captured by Trandoshan slavers and held captive on Wasskah, but he worked with a fellow captive, Jedi Commander Ahsoka Tano, to escape.
In TCW, Anakin briefly saw Chewbacca in the finale of season 3.
As Han Solo, Chewbacca, and Leia were gathered in one location at the same time, Vader and his stormtroopers had the perfect opportunity to take them down. However, because he saw their dynamic as a source of weakness, he opted to spare them.
C-3PO accidentally became part of the Battle of Geonosis when his head was affixed on top of a battle droid's body after a mishap in the Geonosian droid factory. R2-D2 and C-3PO witnessed the secret wedding between Anakin Skywalker and Padmé Amidala on Naboo.
Ahsoka's departure haunted Yoda for some time afterward; he felt extremely guilty and remorseful, partly for refusing to stand by her and partly for placing her on the path that led to her departure from the Jedi Order.
Well, to be literal, she was never mentioned because she hadn't been created at the time Episode III was made.
The second time Yoda mentions his long life is in Return of the Jedi, when he tells Luke, “When you reach 900 years old, you will not look as good as you will.” If we take Yoda at his word, that means the Jedi Master died at the ripe old age of 900.
She also knows Obi-Wan, and she knows him well. Her holographic plea for help, already iconic, will never be the same. She knows Obi-Wan's real name as well as his alias of “Ben.” When Luke comes barging into her cell and says, “I'm here with Ben Kenobi,” Leia jumps off the bunk in an instant.
Yoda survived, however, with the help of natives Chewbacca and Tarfful, who used a hidden shuttle to evacuate the Jedi Master from the planet. In the aftermath, the brave Jedi Padawan Gungi, a survivor of the Jedi slaughter, was returned to what remained of his homeworld with the help of Clone Force 99.
In-Universe Answer: Rey has probably learned Chewie's language or a similar one earlier in her life. Real World Answer: All Star Wars characters are written to be able to understand Chewie to facilitate the story telling. It's one of those things you aren't meant to ponder; just go with it.
After the battle, R2-D2 and C-3PO were the sole witnesses to the marriage of Anakin Skywalker and Padmé Amidala in Lake Country. After this Padmé gave ownership of R2 to Anakin while she kept 3PO.
However, when they next met in Star Wars: Episode II – Attack of the Clones, Anakin and Padmé's feelings for one another grew into something resembling love, and their wedding at the end of the film solidified their relationship as one of the most important romances in Star Wars history.
Anakin and Obi-Wan confront General Grievous on the bridge of the Invisible Hand as it wages battle against Republic warships over Coruscant.
She was framed for the bombing of the Jedi Temple, and later, cold-blooded murder. As a result, the Jedi Order expelled her, and she escaped from prison to clear her name.
But Ahsoka finally meets Darth Vader face-to-face in the Season 2 finale. In the two-part episode, “Twilight of the Apprentice,” Ahsoka accompanies Kanan and Ezra on a journey to Malachor.
At the end of season 5 of The Clone Wars, Ahsoka Tano walked away from the Jedi Order and never looked back again. In the aftermath of being framed for bombing the Jedi Temple on Coruscant, and being abandoned by the Jedi, excluding her own master, Ahsoka grew increasingly disillusioned with the Jedi Order.
Although Ahsoka stresses that the decision to part ways is not because of Anakin, he feels responsible as her Master. It is also another example of Anakin feeling betrayed by the Council. His padawan, who he has grown exceptionally close to, has left him and Anakin feels alone.
Anakin had always struggled with abandonment even though he had left his mother willingly. Seeing Ahsoka leave was like a blow to the heart and his fear of loss is what Yoda and Obi-Wan feared would get the better of him. Years later, his spectre appears to Ahsoka and blames her for his turn to the dark side.
All along the way, Barriss was there to help her friend, leading Ahsoka to different clues and places -- until Anakin Skywalker discovered the truth. It was Barriss herself who orchestrated the bombing and framed Ahsoka.
Both R2D2 and C3PO both know that Darth Vader and Anakin are one and the same. 3PO's memory was erased back in Star Wars Episode III: Revenge of the Sith but was restored by R2 back in Star Wars Episode IV: The Rise of Skywalker. As such, they both remember everything that happened.
This is confirmed later in the movie when Obi-Wan informs Padme that Anakin killed them. Both are torn apart with hurt and confusion, trying to make sense of something so terrible.
What Padmé knew about Anakin's previous dark deeds. Padmé was well aware that Anakin had committed dark crimes that would've started his fall to the dark side. He even confessed to her that he had massacred an entire Tusken Raider village to avenge his mother, leaving no one alive.