I tried importing the Noesis package into several Unity 2018.1 projects and when running any Noesis sample it shows a black screen only. I tried with both the classic standard shader and the new Lightweight Render Pipeline with the same result. Samples work fine in 2017.3.

Is this a known issue?

We didn't try 2018 beta yet. As soon as the official version is released we will provide a compatible version.