The original Resident Evil 2 is notable for its "Zapping" system, wherein the game effectively had four different campaigns, two for each character, that could impact one another. For example, players could go through Leon Scenario A or Leon Scenario B, and player actions in those campaigns would impact Claire's playthrough and vice versa. Anyone hoping to see the Zapping system return for the Resident Evil 2 remake will be disappointed, but the game will still have separate campaigns for Leon and Claire.
As revealed by Resident Evil 2 producer Yoshiaki Hirabayashi in an interview with Game Informer at E3 2018, the team felt the Zapping system from the original release involved too much backtracking and was "tedious for players." Having two distinct stories for Leon and Claire is a way to streamline the experience while still giving players unique situations depending on which character they choose to play as.
While Leon and Claire will have separate campaigns in Resident Evil 2, it doesn't mean that the two characters aren't going to interact with one another. It's likely that the start of the game will be similar to the original release, with Leon and Claire meeting up in the middle of a zombie-infested Raccoon City, and then becoming separated somehow. From there, Leon and Claire will still come across one another at different points in their campaigns, so they should still have some impact on each other's story.
The removal of the Zapping system isn't the only thing that's different about the Resident Evil 2 remake. The most notable change is that the game is switching from the fixed camera angles seen in the original to an over-the-shoulder camera, like the one used in Resident Evil 4, 5, and 6. This change has proven somewhat divisive, but fans should withhold judgment until they get their hands on the finished product early next year.
Once Resident Evil 2 is available to fans, it will be interesting to see if the game lives up to the hype it's generated at E3 2018, and if Leon and Claire's campaigns are able to live up to the quality of their original adventures.
Resident Evil 2 will launch on January 25, 2019 for PC, PS4, and Xbox One.
Source: Game Informer