Does Visibility ease on performence ?

I’m not sure if it’s the right place to ask, but if I turn off the Visibility of an object, would it ease on the performance ?

Yes it does. You can also set cull distance or level of detail etc.
But if its worth depends on situation, what type of actor you want to hide etc.
Sometimes logic to hide/show an actor would eat more than actually hidding it. Ureal is well optimized.