I'm looking for a sci-fi novel written in English and aimed at a teen audience. I read it in print between 2014 and 2018 and it seemed fairly new at the time. I think the cover was pretty dark-colored, but I don't remember more about the cover than that.
The plot starts by introducing five teens who had won some sort of contest and were either already in a space station or going up a space elevator into space. During their time in space, they are subject to an event that results in them each getting a different superpower, although they don't know what's happening at the time. However, the event is recognized as dangerous and causes them to return to Earth right away. The main character is a teenage girl that was in the group and so now has a superpower. These developments cause further strain to their already strained relationships.
I don't remember all of the powers, but I do specifically remember two. The first was a kind of leadership/persuasion power that one of the boys had. The other four teens found it very hard to disobey him and he also gained some form of enhanced cognition/planning. I remember thinking the other power was very unique at the time: a different boy's skin could grow incredibly fast, allowing him to make armor and claws out of it, but it also impaired his movement. Someone else may have had a teleportation or flight power, too.
The five eventually escape from a place where they are being held and end up fighting and killing each other. Killing another releases their power, which can be absorbed somehow by the one that won. Eventually, the main character absorbs all the powers. At some point along the way, she comes to the conclusion that these powers were granted specifically to oppose an invasion by another alien race.
After the main character has all the powers, she finds the invading ship, gets to it while it is heading toward Earth, and digs through the hull to the center. The hull was kind of squishy; she remarks on how the skin growth/hardening power she took seemed to be required for this. When she gets to the center, she destroys the ship. It's also remarked on how all five of them working together would have been much better suited to destroying the ship than just herself alone, but she manages to do it anyway and save Earth.