When asked about how they'd approach Deadpool appearing in one of their Avengers films, directors Joe and Anthony Russo responded that they would first need to lock themselves away for two months before they could even attempt to answer the question.
"He breaks the 4th wall so it changes tones," stated Joe just as Anthony quickly added, " I would tell you this, and this is how we craft all of these moments, we would literally lock ourselves in a room for two months and discuss this question before we could arrive at an answer."
Anthony then went on to address the type of questions they'd ask each other over the course of those hypothetical two months, stating, "Philosophically [we'd investigate], are the new rules with the character, 'Is he not allowed to break the fourth wall? Would that damage the character?' So you have to figure out how you would incorporate the tone of what's happening in the MCU with a character like that."
With Disney's acquisition of 20th Century Fox now final, Disney CEO and Chairman Bob Iger openly confirmed that Ryan Reynolds' Wade Wilson will survive the merger, while the fate of other characters (like Josh Brolin's Cable and Zazie Beets' Domino) remains unknown.