I don’t know if it could be done, the problem is that the network shield blocks at DNS server check level before any request hits the web shield http redirect, so it never gets to a web page being displayed that can be replaced.

What is seen in the first image still shows the domain that was blocked, but the page content is replaced by local content. I don’t know if all those AVs that you mentioned have a network shield equivalent, even GData, which just uses the avast 4.8 scanning engine, I don’t know what other elements it might use.