The precedents with the previous game is that they did not add them at launch and waited for the launch of Fallen Kingdom movie. With this surely the same thing happens but on the other hand, there would still be many months to go before the film was released so I can't be sure.
The question is some species like Dreadnoughtus or Giganotosaurus already appeared in JWE. What will they do with them in JWE2? Will they cut them out from the launch and add them with their movie shapes when the film is released?