Speaking with IndieWire, James Gunn passionately debunked any Hulk/Guardians team-up:
“I can answer that question very easily: it is absolute, 100% bullshit,” he said, adding: “It feels like a great relief to finally say this after all the dumb stuff on the Internet.”
“There’s not going to be a ‘Planet Hulk’ movie, there was never going to be a ‘Planet Hulk’ movie, there was never a plan for the Hulk to team up with the Guardians of the Galaxy â€“ I wouldn’t want the Hulk to team up with the Guardians of the Galaxy! And it’s all a bunch of complete bullshit,” Gunn continued.
But why are the Sakaarans in Guardians of the Galaxy?
“The reason we picked the Sakaraan is because we don’t own Badoon. In the script it originally said Badoon,” Gunn said. “So you can blame search and replace for changing Badoon to Sakaaran and leading to the whole ‘Planet Hulk’ conspiracy.”
So unless he’s lying (and it doesn’t sound like he is) this is a pretty strong debunking to the whole rumor that Hulk will team up with Guardians of the Galaxy in their sequel.