Rings of Power Adds LotR Character; The One You Probably Don't Remember
And you probably don't remember him, because he was hardly a character in either The Lord of the Rings book or Peter Jackson's films.
Círdan the Shipwright who is stated to make his entrance in The Rings of Power Season 2 appeared extremely briefly during the flashback sequence that opens The Fellowship of the Ring, and he shows up again in The Return of the King, just as Frodo and his companions make their departure from Middle-earth.
Both times he's on the screen so briefly that you need to know who his character is from Tolkien's legendarium lore, and specifically look for him, to figure out that this guy is not actually supposed to be a random Elf extra.
And while Círdan was quite important in that lore, being one of the oldest and most learned Elves in Middle-earth, who lived there from its First Age to Fourth, and presumably was going to become the very last Elf to leave Middle-earth, his actual role in The Lord of the Rings ' text was hardly bigger.
So, basically, showrunners have blank sheet of a character to work with – the only hard fact about Círdan, besides his place of residence, is him being a shipwright (even the name Círdan actually means "Shipwright" in the elven language), who builds ships on which Elves can leave Middle-earth.
His appearance in the show was announced simultaneously with announcement of Season 2 being in production so he probably is going to be a relatively important character. Well, at least we can say for sure that he's going to get more screentime than he got in Jackson's films. And that's about all we can say for now, given that he hasn't been cast yet.
As to when we can expect to see him on the screen, and meet the rest of the cast again, while filming of Season 2 had already began, according to the showrunners it could go for another couple of years, which would be unsurprising, given production values of the series. So we probably should not expect the new season of The Rings of Power until fall of 2024.