Definitely not. Plants vs Zombies is a video game franchise, while The Comic Avenger seems to be an unrelated comic series. They don't share any common elements or storylines.
In some fanfictions, the 7th Avenger could be a time - traveler from the future. This person has come back to prevent a major disaster that the Avengers couldn't handle without their help. They know all about the future events and use this knowledge to guide the team, but also have to be careful not to change the timeline too much.