Baking: hard edges issue

What the issue looks like (bake result):

Image of low-poly:
https://shorturl.at/oQjhM

Image of high-poly:
https://shorturl.at/Wdhvy

I tried applying sharp edges only to seams (as I usually did with baking in other programs) and I tried to use fully smooth shading too - nothing worked out. I would appreciate any help!

Welcome!

I know it’s an old post, but I just stumbled on this and can explain if someone has the same problem.

For a normal map that covers the entire object, you would bake with the object completely smooth shaded, then apply the normal map still on that smooth shaded object. It will look wrong in solid view, but the normal map will fully take care of the shading and it will look right once it’s applied.

However, there is a limit to what a normal map can do, it’s not a miracle. The low poly mesh should probably have a little bit of bevel to make it closer to the high poly’s shape for better results.

Also, make sure the normal map is set to non-color, or it will look wrong.