Rumors had come out before of Hayden Christensen making an appearance in the Obi-Wan Kenobi series, and though we don't have any official details from Lucasfilm, new word is going around that Christensen is definitely in the show, and we have specifics on his appearance.
According to Kessell Run Transmissions, the Kenobi series will have a heavy emphasis on flashbacks and their source (who has delivered before) has confirmed that Christensen will be donning the armor that Anakin wears in The Clone Wars.
Admittedly KRT has run into some trouble after they reported that the Mandalorian Season 2 teaser would debut this weekend; but they have delivered reliable news before (specifically Bad Batch news), and last weekend has opted for them to stop reporting on announcements and just report on more substantial news about from behind-the-scenes.
Going back to Christensen though, his return for Star Wars seemed inevitable, what with him making a voice cameo in The Rise of Skywalker and appearing in Star Wars Celebration. Though he was heavily bashed for his work when the prequels came out, he is now one of the most beloved actors in the fanbase, and people can't seem to stop talking about how much they want Anakin Skywalker to make a return.
Hopefully this time Christensen can do a lot more effective acting when it comes to showrunner Deborah Chow. George Lucas is said to be notoriously uncommunicative as a director, so it would be great to see what Christensen can bring to the table working with someone else at the helm.
No release date has been set for the Kenobi series, but it is expected to come to Disney+ sometime in 2022.