I already found out that this (title) is not really possible at the moment at UE4 which is a big, big drawback.
It’s not possible to create realistic water or glass without this feature.
I really don’t want to point the finger here but please check out Unity5 Glass shaders…
In my case the problem are underwater bubbles.
Refraction and transparency works, but without the specular highlight the effect looks not convincing.
Will there be an implementation of Spec Highlights on transparent materials in the future? I think it is a very important feature.
Is there at least any way to fake the effect?