Fox has been hinting at a New Mutants movie since at least 2012 (see “’New Mutants’ Movie in the Works”), and bringing in the younger hero team, created by Chris Claremont in 1982, would make a nice complement to its X-Men, Wolverine, and now Deadpool franchises.
Boone is backed up with The Vampire Chronicles, based on the Anne Rice novels, and The Stand, based on the Stephen King novel, so if production does move forward with Boone, it will be a while before New Mutants begins shooting.