Blurry Landscape Texture even with 8k

I tried many things to get a crisp and sharp landscape texture, but no luck yet.
Maybe someone here can help and point me in the right direction?

I downloaded a texture from megascan and put it into the landscape material, but however if I change it to 4k or 2k texture, there is no improvement in the visual quality.

Others suggested to experiment with mipmaps, anti-aliasing methods, screen percentage and so on, but nothing helped. The textures stays lowres and blurry.

Here is a comparison of the original 8K texture and the inengine one.

Thanks alot for any help.
Best regards