Hulk is one of the heroes surviving after the Avengers: End Game. Yet the future of the Hulk seems bleak as there is still a solo movie offer remaining with Universal Studios, but no talks about it or no guest appearance in any other movie is mentioned. Mark Ruffalo has promised that he would come back as the Hulk.
There are few ideas as to how Hulk would return.
Hulk may come back as a calm figure. In the Avengers: End Game, Hulk has overcome his anger issues. Fans have named him Professor Hulk. Mark Ruffalo also said that he would like to see Hulk with new characters and in a new light. Maybe She-Hulk is the new character who is soon getting her MCU series in Disney+.
She-Hulk, Jennifer Walter, is a cousin of Bruce Banner. She was in an accident and received blood from Banner. The blood transfusion resulted in her becoming She-Hulk. Jennifer, unlike Hulk, is a calm person and a lawyer. She goes about her business as Hulk. The jury may be surprised at her sight. Hulk may be seen in the She-Hulk TV series which might be the end of the contract with Ruffalo. She-Hulk would need some guidance adapting to the hulking form of her life and how to control it.
The last movie possibility also holds that the Hulk would return as the Hulk villain that he was. Edward Norton played the role. There are still a few loose ends of this character. Abomination and the Leader can also be brought back although it might require pulling some strings or strike a deal with Universal Picture. The characters can make their appearance in the She-Hulk series which would give a reason to bring Hulk back.
Lastly, the Immortal Hulk. Hulk can be written or interpreted in many different forms when being written by different writers. In the Immortal Hulk, the character has or gets a spin every time he dies. The Hulk can be brought in any way possible. It may be as mentioned above or in some new way. Whatever be the way, it should be entertaining, and fans are looking forward to it.