Low Poly Help

Hello, i have started using Zbrush to make assets for my game. The problem I am having, is that when I make my models low poly, even with the normal maps, they just simply don’t look how they did before I reduced the poly count. I know that it wont capture 100% of the detail, but my stuff isn’t looking near as close to it as it should. The edges are triangulated in unreal engine and in substance painter, it looks like a giant blob. All of my models are doing this. Any suggestions? Thanks! I attached some images of what I am talking about. I can supply the files if needed.