The button mapping and the usage too as there is a slight delay in action.
When we go to other regions the camera is sometimes taking a lot of time to change from one to the other.
I recommended playing with a controller - if you can - if the button mapping on the keyboard is not comfortable for you. If you are talking about the delay in attacking, that is intentional.
If you change regions - not rooms - there is a screen transition and also a title card showing you the name of the area, are you talking about that in regards to the camera being slow?