With Deadpool soon to debut in the MCU in Deadpool 3, the third movie in an R-Rated trilogy, it seems the MCU's dry spell of R-Rated content is ending. The franchise has famously shied away from entertainment harder than a PG-13 rating during most of its previous phases, but it is officially ending with a good precedent to back it up.
After the immense success of previous R-Rated Marvel projects such as Blade, it is improbable that the MCU will avoid this adult content forever. Especially due to the high volume of characters existing or soon to exist in the universe who are well suited to this format.
Deadpool
Deadpool is a highly comedic, fourth-wall-breaking mutant member of the X-Men and The X-Force who possesses an extreme healing factor that essentially makes him immortal, gifted to him during his time in the Weapon X program.
Fox released both Deadpool 2 starring Ryan Reynolds as the character, which we were both R-Rated and made just over $700 million each at the box office. Due to Deadpool's proven success in R-Rated movies, it would be foolish of Marvel to not allow the character to continue in this format, especially if these two movies are canon to the MCU's Deadpool 3.
Blade
Blade is a dhampir who trained to become the perfect vampire hunter and swore to rid the world completely of vampires. Blade has previously starred in an R-Rated, cult classic trilogy that made over $400 million, proving he is well suited to this age rating.
Blade will be ing the MCU in Phase 5 portrayed by Mahershala Ali in Blade, which would work incredibly well as an R-Rated movie due to Blade's violent and explicit nature. Allowing the character access to violent fight scenes, extreme gore and explicit one-liners would display true respect for the source material and undoubtedly catapult this character into the limelight once more.
Wolverine
Wolverine is an extremely popular mutant member of The X-Men who is famous for having an extreme healing factor alongside a pair of retractable Adamantium claws.
Wolverine has previously appeared in the R-Rated Logan, which was met with incredible critical success and a box office gross of over $600 million. With a character premise based upon rage, guilt, and trauma, Wolverine is perfectly suited to R-Rated content, especially due to his history as a soldier and a samurai, which are elements of his character the MCU may explore, potentially within an R-Rated rating.
Moon Knight
Moon Knight is the superhero identity of ex-mercenary Marc Spector who was gifted superpowers by the God Konshu. Spector shares his body with his other personalities Steven Grant and Jake Lockley who also help fight crime in their own way.
Moon Knight debuted in the MCU in the TV-14 rated show Moon Knight. Due to the show's age rating, it could not delve into the violence and adult themes typically displayed in Moon Knight comics. However, Moon Knight will undoubtedly appear in future MCU projects, including future solo projects, which would do the character justice if R-Rated by effectively conveying how unhinged the character truly is.
Ghost Rider
Johnny Blaze became Ghost Rider after being infused with the Spirit of Vengeance granting him many supernatural abilities, including the ability to control Hellfire and the Penance Stare, which he uses to serve justice.
After a Johnny Blaze Easter Egg appeared in the She-Hulk trailer, it seems a Ghost Rider debut may be occurring soon. This character would excel in an R-Rated project, not only because of his gruesome origin story but due to his affiliations with the supernatural and his tendency to kill evil-doers in grotesque ways. Alongside Blaze, Robbie Reyes and Danny Ketch are also Ghost Riders who would too excel in an R-Rated, live-action environment if given the chance.
The Hood
Parker Robbins, later known as The Hood, is a supervillain appearing in Marvel Comics who stole the cloak and boots of a demon he killed, that granted supernatural abilities upon wearing them.
It seems The Hood will be debuting in the MCU soon in Ironheart after leaked set photos show Anthony Ramos as the character in a comic-accurate costume. Due to the character's brutal and villainous nature alongside the grotesque demons and monsters he battles, The Hood would fit perfectly in a future R-Rated project after his run in Ironheart, possibly alongside other villains such as Agatha Harkness.
Sentry
Robert Reynolds is a former meth addict who gained the power of a million exploding suns, turning him into Sentry, an extremely powerful entity with unfathomable power. This power has a serious consequence in the form of The Void, an evil parallel to Sentry's powers that causes an act of malevolence for every act of benevolence Reynolds carried out.
In an R-Rated setting Marvel could effectively show Reynold's history of mental illness and drug addiction, later showing how baseless and unhinged the character can be as a result of his extreme power, which has led to several catastrophes in the comics. The Void would also work incredibly well in this setting too considering its pure evil nature which has led to the violent deaths and injuries of many.
The Kingpin
Wilson Fisk, better known as The Kingpin, is a mob boss who rules over New York City with an iron fist, using his extreme strength, size, and stature alongside his martial arts skills to accomplish this. Wilson Fisk recently made his MCU debut in Echo, with leaked images showing Fisk on the set of the show.
D'Onofrio previously portrayed the character in the incredibly successful Goodfellas, in of the realistic depiction of mob violence and power struggles shown in both movies.
Spider-Man Noir
Spider-Man Noir is an alternate version of Spider-Man from the Noir-universe who transformed into the Spider-Man during the great depression to take on the mob responsible for killing his Uncle Ben, later fighting The Nazis. This Spider-Man is unlike no other due to the fact he is armed to the teeth with firearms and will kill in certain cases, using brutal and lethal force against his enemies if necessary.
This character is prime picking for a future R-Rated, Noir-themed project due to the characters' initial violent depiction and associations with crime gangs and The Nazis in the comics. After Spider-Man: No Way Home debuted a live-action, Spider-Man-themed multiverse to screen, it seems possible for a Spider-Man Noir movie to be greenlit and take place within another universe, especially due to Sony's push of Spider-Man content with the SPUMC.
The Punisher
The Punisher is an ex-marine who wages a one-man war on crime after the death of his wife and children at the hands of the mob. In his campaign against crime, The Punisher employs brutal methods of murder, kidnapping, violence, coercion, and torture to take out those he deems worthy of punishment in order to serve justice to the criminal underworld.
The Punisher is the definition of a character who needs an R-Rated project in the MCU due to his violent nature and brutal backstory. The character has been seen in live-action in 3 R-Rated movies previously and was most recently played by Jon Bernthal in The Punisher which was rated TV-MA. If rumors are to be believed, Bernthal will reprise his role as the character in the MCU, hopefully in an R-Rated setting which would allow him to be as comic accurate as possible, delving into his backstory as a soldier and allowing him to carry out his violent tendencies in all their morally ambiguous glory.
