The lore in Star Wars is some of the most expansive material ever seen in media, with nearly every character given a full backstory in some form or canon or Legends material. Before Disney took over Lucasfilm and began producing more content, many characters throughout the timeline had unknown fates, with the likes of Boba Fett and Darth Maul among them.
Now with a multitude of projects that can fill in gaps, Lucasfilm has plenty of opportunities to tell interesting, new stories for these characters, perhaps taking them out of the weird limbo they're stuck in. Which characters don't have clear conclusions as of yet?
Quinlan Vos
Obi-Wan Kenobi featured a multitude of Easter eggs and references, even including a namedrop for the fan-favorite Jedi Quinlan Vos. Outside of his brief appearances in The Phantom Menace and The Clone Wars, not much is known of Vos in Canon. His Legends counterpart on the other hand has a long history in which he trained Aayla Secura and was an integral player during the Clone Wars.
Initially slated to appear in a new story arc for The Clone Wars, these episodes would end up being adapted as the novel Dark Disciple. He was on Kashyyyk when Order 66 occurred, but his whereabouts past 10 BBY (the events of Obi-Wan) are unknown.
L0-LA59
L0-LA59 (better known as Lola) appears as Leia's droid in Obi-Wan Kenobi, but by the time of the original trilogy, Leia is shown to have R2-D2 in use as her droid.
While Lola was a fun addition to Obi-Wan and a cool new droid, it can only be assumed by some point that the droid was either destroyed or just no longer in active use. Perhaps if another season of Obi-Wan comes to fruition, viewers could see the droid once again.
Jar Jar Binks
Regarded by many as one of the most controversial Star Wars characters, Jar Jar has had a divisive reception to say the least. Following the end of the prequel trilogy, many were unsure of the character's fate, but the novel Aftermath: Empire's End offers closure for him. Following the New Republic's victory against the last forces of the Empire, Jar Jar was once again exiled by his people.
They felt he was responsible for causing the Empire as he persuaded the Senate to give Palpatine emergency powers. He becomes a street performer as a clown, where he is sadly hated by most of the townspeople but loved by the children. All seems lost for him until he meets a boy named Mapo who asks Jar Jar to teach him to become a clown. This gives Jar Jar newfound purpose and an optimistic future. His status by the time of the sequels is not known.
Commander Cody
Following Order 66, Commander Cody remained compliant with the Empire, but his activities as a stormtrooper are not known. His Imperial days are an important event from Canon that fans really want to see on-screen. All that is known is that he and the 212th aided in the Empire's slavery camps for Wookiees on Kashyyyk.
Luckily, fans won't have to wait too long to see him in the Empire, as he is set to appear in the second season of The Bad Batch, releasing on Disney+ on September 28th. It'll be interesting to see how he reacts to the redeemed Clones who left the Empire.
Mon Mothma
Although brief, Mon Mothma made a memorable appearance in Return of the Jedi as one of the few named women who appear in the Original Trilogy. Following the end of the Galactic Civil War, she became the first Chancellor of the New Republic.
After some point, she stepped down, but she is nowhere to be seen by the time of The Force Awakens. She'll soon reappear in Andor, taking place 5 years before A New Hope and Rogue One, but it would be fascinating to see what she was up to around the era of the sequels.
Ezra Bridger
Following the Rebels finale, fans have continued to theorize where Ezra and Thrawn could have gone. By the time of The Mandalorian, which takes place 5 years after Episode VI, Ezra's whereabouts are still unknown, meaning he has been missing for nearly 8 years.
While it was initially rumored that an animated sequel series would follow Rebels, Ahsoka seems to be the place where this story thread will continue, and given Ahsoka's desire to find Thrawn, it seems like a given that Ezra's status will be resolved one way or another.
Yaddle
Besides Yoda and Grogu, Yaddle is the only other known person to be of the same mysterious species. It could very well be that she and Yoda are Grogu's parents (or some other relation), but that remains to be seen. Like Yoda, she herself is much older than most Jedi, being close to 500 years old.
Following her only appearance in The Phantom Menace, she was never seen again. At some point before the Clone Wars, Yaddle stepped down from the Jedi council, with her seat taken by Shaak Ti. It would be very captivating to know what happened to her and why she left the council.
Barriss Offee
Like Yaddle, Barriss Offee only appeared in a single film as well, in Episode II. The Clone Wars did an excellent job explaining her absence in Revenge of the Sith where she was taken into custody after bombing the Jedi temple.
Her actions caused Ahsoka to be framed and resulted in Tano leaving the Jedi Order. After being taken away, Offee is never seen again. That could change, as The Illuminerdi reports that Ahsoka will see the return of Barriss Offee. This could further flesh out her character and offer an interesting reunion between her and Ahsoka.
Grand Admiral Thrawn
"The Jedi" episode of season 2 of The Mandalorian planted seeds for Thrawn's return as Ahsoka demands the whereabouts of the Magistrate's master, who is revealed to be Grand Admiral Thrawn.
While already well into production, Thrawn is expected to return in Ahsoka as part of Lucasfilm's grand plan for the Disney+ Star Wars crossovers. Though casting details remains unknown, fans are thrilled at the thought of seeing Thrawn in live-action and look forward to seeing who they cast as the iconic villain.
Mace Windu
While many consider him to be canonically dead, both Samuel L. Jackson and George Lucas maintain that he survived the fall out of the Chancellor's office, per SlashFilm. As seen in many forms of Star Wars media, Force users tend to be able to survive massive falls.
Many fans theorized Mace Windu would make an appearance in Rebels as it was airing, but for a character like Windu, this should definitely be saved for a live-action project for a bigger effect. With an actor as passionate about the role as Samuel L. Jackson wanting to return, Lucasfilm should certainly listen. He would make for a great adversary against Boba Fett.