Hope: Deadpool 2 & Dark Phoenix

The Merc with a Mouth is gearing up to return to our screens next year, and he's gonna have some company in the form of Josh Brolin's Cable. The time-traveling mutant was unveiled by Ryan Reynolds on Twitter, and his full costume has already sparked speculation that Hope Summers — Cable's omega-level mutant daughter — will enter the X Men movie universe in Deadpool 2.
Cable's costume includes a ragged teddy bear hanging off his belt, implying that he's partway through his search for Hope, as they got separated while being pursued by would-be assassins. Hope's arrival was also foreshadowed in the Deadpool 2 teaser, as the word "HOPE" was scrawled on the telephone box wall.
So what does this mean for the X-Men movie continuity? As in the comics, Hope's entrance will likely be accompanied by huge, world changing events — not to mention the arrival of the Phoenix Force.
Hope Is The Phoenix Force
Known as the "mutant messiah", comic-book Hope Summers has always carried the weight of an immense destiny to either save or doom the mutant race. The first mutant child born after Scarlet Witch's "no more mutants" spell, Hope is a power mimic, and can also intensify the powers of those around her. She spent her early life running through time with Cable, who adopted her as a baby, and later on her destiny was revealed when the Phoenix Force came to claim her in Avengers vs X-Men.
In this arc it soon became clear that Hope is part of the Phoenix Force itself, explaining her lack of a father, why she had powers despite Wanda's spell, and her physical resemblance to Jean Grey. This also allowed Hope to not only absorb the Phoenix Force, but resist its desire for destruction and finally dispel it with a little help from Wanda — which also ended the "no more mutants" curse.
This was a thrilling end to a tale that began with the Dark Phoenix Saga, in which Jean Grey was first possessed by the Phoenix Force, leading her to cut a huge swathe of destruction across the galaxy. And that's where the movies come in.
Tying Into Dark Phoenix, Setting Up The Future
We've known for a while that the next X-Men movie will adapt the Dark Phoenix Saga, as Sophie Turner's Jean struggles with the cosmic entity. This will allow the filmmakers to begin a story that had a huge lasting impact on the comics, and may even ripple out into Deadpool 2. We still don't know exactly how Hope was created and why she's part of the Phoenix Force, so the film X-Men: Dark Phoenix could plant hints about this, even showing young Hope being born.
Of course, Deadpool 2 is set to release about six months before Dark Phoenix. It's possible that Hope's significance as part of the Phoenix, not to mention the "mutant messiah" will only be alluded to in Deadpool 2, foreshadowing the saga's beginning in X-Men: Dark Phoenix.
It seems highly likely that Deadpool 2 won't be Hope's only appearance in the movies. As an omega level mutant, Hope's story has lasting implications for every mutant alive, and stretches from the past to the apocalyptic future. She could end up joining the X-Men in the main movies, or even the New Mutants. But if I were in charge of the X-Men franchise I know exactly where I'd put her: In an X Force movie set in the future, with X-23 leading the team that debuted as children in Logan.
Basically, Hope's inclusion in the franchise comes with a host of exciting possibilities, allowing the filmmakers to finally tie Deadpool into the main continuity, plant hints about future team-ups, and adapt one of Marvel Comics' all-time best sagas. Unfortunately though, this franchise has a habit of throwing in big-name mutants just for a cameo (remember that time Emma Frost was Wolverine's wife's sister?), so here's hoping they break this tradition to do Hope Summers justice.