You can do it in Unreal by using a class derived from the motion controller and changing the logic on the rendering thread or by throwing out components that you don’t want updated in the “GatherLateUpdateComponents” function. It is no harder than unity if you are using code.
In blueprint there isn’t a current way no.
Aiming through sights is better with late updates honestly though (the end location of the shot is closer to where the sight is), it is generally your own shakiness that gets in the way there unless your tracking has serious tremors.
Edit I will say that the worst problem with gun tracking with the controllers is the tracking wobble introduced when pressing the trigger. If you let the trigger snap back up it actually introduces enough vibration into the body that the internal positional sensor freaks out and throws out bad values for a moment.