One thing I’ve noticed is that occasionally UE4 will freak out and cause the performance of your game to drop drastically. You’ll experience noticeable lag and tons of error in the output log if you’re using c++.
One way that this might be fixed is by turning off UDP messaging.
Go to Project Settings->Plugins (At the bottom of the scroll bar)->Tick “Enable Transport” to off
This should make any stutters you have go away.