Cage baking / top only
both 4k normal map images scaled down to 1024px
the second normal map ist baked with cage
Hardly to see on the screenshot but now there is a difference- have a look to the lower edges
Normal Map and top-part / second one with cage
https://gyazo.com/79c2f9f977de3aaab0ef5e5d2edb83d5
https://gyazo.com/065223633d9fba3b331f0884132b217f
I had the idea to work with several UV maps;).
But for now I stop testing and bake my normals.