Clint Barton has been a fan favorite character ever since his first appearance in 2012's The Avengers, all the way through to his recent spin-off show Hawkeye. He's an integral part of the original Avengers roster, but after the events of Avengers: Endgame, the character's future has been somewhat up in the air.
It hasn't yet been confirmed whether or not we'll see Barton return at all, but the events of Hawkeye seem to indicate that the character isn't quite done with his superhero persona just yet. Although his family is clearly the most important thing to him right now, there's nothing stopping the character from returning in the future, particularly with the possibility of Kate Bishop following in his footsteps.
Doctor Strange in the Multiverse of Madness
It's likely that Renner's return as the character would have already been confirmed in a project that's due to release so soon, but nothing is impossible with the MCU - particularly with this Doctor Strange sequel, where rumors claim audiences will see many returning characters back on their screens.
The cosmic side of the MCU is something that Barton's character has never really explored before, but Multiverse of Madness could be a fitting gateway to introduce this. His close friendship with Wanda Maximoff seems the most likely route for his introduction here, though audiences haven't seen the two interact too much lately.
The Falcon and the Winter Soldier: Season 2
Although the second season of Sam and Bucky's solo series is yet to be confirmed, the introduction of Clint Barton's character could be an interesting route to take. If the second season does come to pass, it seems likely that much of the central conflict will come from Contessa Valentina Allegra de Fontaine, who seems to have some interest in Hawkeye based on her appearance at the end of Black Widow.
Her involvement in this series could pave the way for not only Hawkeye to be introduced here but also Yelena or Kate Bishop - both of whom played large roles in the Hawkeye series. However, their stories seem a little too distant from Sam and Bucky's narrative at the moment for this to be likely. Still, not impossible.
Ant-Man and the Wasp: Quantumania
With the exception of their journeys into the Quantum Realm, the stories of Scott Lang and Hope van Dyne seem fairly rooted in the real world so far - much like Barton's. As one of the last remaining original Avengers, Clint could act as a source of help and wisdom for the duo in their third solo film.
Although Clint and Scott haven't shared many scenes together outside of the larger battle sequences, actors Renner and Rudd are known to be close friends off-set, which could bring a fun dynamic to the two characters if they were to team up in Quantumania.
She-Hulk
There's very little that's known so far about the upcoming She-Hulk series, other than the involvement of both the title character and Bruce Banner, who will likely play some sort of mentor role for titular Jennifer Walters. As the only two remaining on-world original Avengers, Banner and Barton could easily come together in this series.
However, it seems likely that She-Hulk is going to act primarily as an origin story for that character, much like Hawkeye was for Kate Bishop. It's a stretch to imagine that Barton will play a large part in the series, but a small cameo is never out of the question.
Ironheart
Disney+'s Ironheart won't be hitting screens until at least the end of this year, but it's definitely possible that the series will include several allusions to the original Avengers that the title character will most likely take inspiration from. Hawkeye could definitely be one of these inspirations for her, and a brief appearance certainly isn't off the cards.
Much like She-Hulk, Ironheart is also set to act mostly as an origin story for Riri Williams, a character known in the comics for her sharp intelligence and reverse-engineering of Tony Stark's Iron Man armor. Barton's relationship with Stark could definitely serve as a point of entry for the character in this series.
Armor Wars
The upcoming Armor Wars on Disney+ is a more likely candidate to house Renner's return as Hawkeye, namely because of the show's proximity to the legacy of the original Avengers. The story will primarily follow James Rhodes as he attempts to prevent Tony Stark's tech from getting into the wrong hands.
Armor Wars could end up being an effective and exciting way of bringing back the remaining members of the original Avengers to help fight against the unknown force that is threatening their legacy - and Clint Barton would be an important part of this. As a close friend of Tony Stark, it's likely that he would be willing to come out of retirement and don the mantle once more for a threat like this.
Fantastic Four
As far as Marvel Comics are concerned, wherever the Avengers turn up, the Fantastic Four aren't too far behind. That hasn't been the case for the MCU, however, which has been unable to introduce the iconic family due to ownership issues that have recently been resolved - meaning that Mr. Fantastic and his crew will finally be arriving in the MCU in their own solo movie at some point soon.
Since the Avengers and the Fantastic Four are so strongly connected in the comics' history, it would seem sensible to have some sort of reference to the Avengers in their cinematic introduction. Hawkeye could definitely play this role, filling in the absence of Tony Stark or Steve Rogers.
Captain America 4
Although there's very little that's known about the film so far (other than Sam Wilson's involvement as Captain America), it seems very likely that the fourth installment in this series will be an extremely important one in the long run of the MCU.
Since the Captain America movies have always been fairly big events, it seems safe to assume that the fourth will be no different, likely bringing back several characters that audiences know and love to tell an exciting and large-scale story. Due to the large role that he played in Captain America: Civil War, it's not impossible that Clint Barton will be one of these characters.
Echo
Since the character of Echo was so prominent in Hawkeye, it's only fitting that Barton's character would have a similar presence in her show. There's plenty of speculation surrounding the plot of Echo, but it seems likely that either Kingpin or the Contessa will serve as the central antagonist.
Kingpin obviously has connections to Barton's tenure as Ronin, and the Contessa is a character that has strong ties to both Nick Fury and S.H.I.E.l.D. in the comics - so it seems very likely that Hawkeye would fit in perfectly in this story.
Hawkeye: Season 2
The second season of Hawkeye is yet to be confirmed, since the show was originally set to be a limited series. However, Disney's Loki was also only set for one season, but the positive audience reception has since pushed it to an official second outing. If Hawkeye manages to do the same, Barton will almost definitely return here.
There are plenty of possibilities for a second story surrounding Barton and Bishop, since the pair have so much in common and so much charisma on the screen. Whether it's a return to Kingpin, Echo, or something much more extreme, watching these two characters come together again would be a perfect way to drag Barton out of retirement one last time.