Marvel Studios recently announced that they will be adapting the popular comic storyline, Secret Invasion, which sees the alien race of the Skrulls infiltrating every major area of power. It was also confirmed that, rather than making it a movie as they did with Age of Ultron or Civil War, it will be a series on Disney+.
While it was also revealed that Talos and Nick Fury will be the leads of the series, there are a bunch of other characters from both the wider MCU and from the comics that the series could introduce to mainstream audiences.
MCU: Soren
Soren is the wife of Talos and was introduced alongside him in Captain Marvel as one of the Skrull refugees hiding in Mar-Vell's lab. She last appeared in Spider-Man: Far From Home, posing as Maria Hill while Fury was away.
She and her husband were shown to work well together, so it would make sense if she had a part to play in the series. Like the other Skrulls, she is capable of shapeshifting so she could be a great double agent to spy on and monitor the invading forces.
New: Agent Brand
The government's newest agency, SWORD will seemingly have a big role in the MCU going forward after being introduced in WandaVision. In the most recent episode, it was revealed that the organization is currently being led by Tyler Hayward after the death of Maria Rambeau.
While the focus of the agency seems to be on sentient threats on the show, in the comics, the organization focuses more on extraterrestrial ones and is led by a human-alien hybrid named Abigail Brand. Due to her tongue being able to make shapes that normal human tongues can't, Brand is multilingual and is able to speak in several languages most notably Kree and Skrull. While it doesn't seem like she will be in WandaVision, she could make her MCU debut in Secret Invasion
MCU: Captain Marvel
Carol Danvers aka Captain Marvel is the most powerful and most recently-added hero in the MCU. She was last seen at Tony Stark's funeral and was confirmed to be off-world by Talos posing as Fury in Spider-Man: Far From Home.
It would make sense if she was a part of the series considering her friendship with Talos and Fury plus she has a lot of experience fighting Skrulls because of her time as a Kree soldier. Since she was responsible for helping the Skrulls find a new homeworld at the end of her movie, her personal connection to the species could be an interesting dynamic to explore.
New: Veranke
In the comics, Veranke was the Skrull Empress who initiated the invasion and while there's a good chance she'll debut in the series, it's just as likely that she's already been introduced.
Near the end of Captain Marvel, the movie reveals that there are a bunch of Skrulls living in Mar-Vell's laboratory, including Talos' daughter. She is never given a name in the movie so there is a decent chance that she could actually end up being Veranke which would add another layer of emotional impact to the story.
MCU: Monica Rambeau
Monica Rambeau was introduced in Captain Marvel as the 10-year-old daughter of Carol's best friend, Maria. She has most recently appeared in WandaVision where it's revealed that grew up to be an agent of SWORD, an organization founded by her mother.
In the comics, Monica gets powers of her own and becomes the hero, Spectrum. Since it seems like SWORD will likely play a role in the series, there is a good chance that Monica will as well. If the main villain does end up being Talos' daughter, it would make even more sense considering the friendship the two formed.
New: Kl'Rt
Super-Skrull is one of the most popular Skrulls from the comics and one of the strongest members of the alien army. While most Skrulls can only replicate physical features, others can replicate superhuman powers as well.
Kl'Rt has the ability to mimic the powers of the Fantastic Four including Mr. Fantastic's elasticity, the Invisible Woman's invisibility, and force field creation, the Human Torch's pyrokinesis, and the Thing's extreme durability and strength. While the team has not been introduced in the MCU yet, they could appear before the series to establish the powerset.
MCU: Maria Hill
Since her introduction in The Avengers, Maria Hill has been Nick Fury's right-hand woman so it would make sense if she appeared in the series with him. She was impersonated by Soren in Far From Home meaning the last time the real Maria Hill was shown was during Infinity War after being snapped away by Thanos.
She has proven herself to be extremely loyal and resourceful so it would help if Fury had at least one person he could fully trust with him. There is also a great chance that she could be a Skrull in disguise herself which would be a pretty powerful twist considering how important she has been in the franchise.
New: Hulkling
Dorrek VII is a Skrull-Kree hybrid and the son of Kree Mar-Vell and a Skull Princess named Anelle. Since he is a hybrid, Hulkling has a mix of powers and abilities from both species meaning that he has enhanced strength, durability, and is able to shape-shift, usually giving himself a pair of wings to fly with.
Since the MCU seems to be leading up to the introduction of the Young Avengers and Hulkling is one of the original members in the comics, his inclusion would make sense. He also is in a major relationship with Wanda Maximoff's son, Billy, and the two even got married in the comics, so it would be great to finally see that relationship on screen.
MCU: Quake
Fans of the MCU have constantly been asking for more crossover between the Marvel Studios projects and the Marvel television division. The best way to kick that off would be to have one of SHIELD's best and most powerful agents appear in the series, Daisy Johnson.
Johnson aka Quake is an Inhuman that has seismic powers and was the main character of the show, Agents of SHIELD. She joined the organization after being recruited by Agent Coulson, and after dealing with her team being replaced by Life Model Decoys and facing the Chronicoms, an alien race with face-stealing technology, she is absolutely equipped to deal with a Skrull invasion.
New: Kly'bn
Like with the humans of Earth, the Celestials also traveled to the Skrull homeworld and experimented on their citizens creating 2 new races of Skrulls, Skrull Deviants which could shapeshift, and Skrull Eternals that possessed immense cosmic abilities.
According to the Book of Worlds, which is basically the Skrulls Bible, a Skrull named Kly'bn is the last Eternal. Since the book also claims that Earth belongs to them leading to the invasion in the first place, it would be a safe assumption that the Skrull God might appear.