A quick fix for this issue to my mind is wider water texture blending, less saturation, more value. I see that the water texture looks very close to vanilla. But you use realistic textures and compared to them water looks more cartoonish. You will never see a dark blue water like this IRL.
A long way is to write a custom water shader (or make it in any shader editor for Unity). Separate a plane in two. First for the ground. Tessellation + displacement from height map. Second for the water. Animated normal map (two procedural cloud textures of different scale moving in different directions), fresnel, transparency, refraction. Reflection would be great, but I don't know how to make it in Unity as the engine uses reflection probe system. Perhaps it can be done via Shader Graph also, but it is a real pain for gpu.
NB: Shader Graph is free but it doesn't offer tessellation node. Amplify Shader does have tessellation but this editor is pricey for just an experiment. But there is a Unity documentation for writing shaders including tessellation and displacement and it's free.
Half of what I wrote I know only in theory. And I may be completely wrong with all these thoughts. Just trying to help.