https://www.pcgamer.com/monster-hunter-world-update-adds-new-mouse-control-options/

The Monster Hunter: World mouse and keyboard controls were not quite perfect when the game released last month, but a new update promises to smooth things out a bit by adding new mouse control options for the in-game camera. The new control scheme, which Capcom said "is in line with the control standards for most PC games," can be accessed from the Controls tab of the Options menu. 

The update also changes the location for the "Relish the Moment" event quest to Elder's Recess, "to improve playability." The quest itself remains unchanged, however.