Cursed Cruise by Victoria Fulton

From the authors of Horror Hotel, called "fast-paced and freaky" by #1 NYT bestselling author Kendare Blake, comes another addictive YA horror about a group of teen ghost hunters who are invited to travel onboard a haunted historic cruise ship.
All aboard...
After their fateful stay at the Hearst Hotel, the Ghost Gang is back with more spooks and more subscribers. They've been invited to record onboard the RMS Queen Anne, a transatlantic luxury ocean liner with a colorful past of violent deaths of hundreds of passengers-souls that bought a one-way ticket to the afterlife (and never disembarked).
When Chrissy, Chase, Kiki, and Emma board the ship, they have a funny feeling they've been sucked into a ghostly time warp-a theory that takes a frightening turn when Chrissy goes missing on the first night.
Unbeknownst to the rest of the group, Chrissy has been sucked into another time by a passenger who wants the Ghost Gang to know her untimely death was not an accident and the perpetrator is still alive-and on board this ship.