Modern house, approx. 160 sqm, optimum in space and usability

So you only have the enormously tall neighbor at the bottom left and at the top right one (with the terrace marked South and West)? Where no houses are drawn, are there none? Or are there? Here in Munich, people would be licking their fingers for a property like that ;-)

Guys, I think he got it, neighbors are great, etc.
But if in the original post the OP's subjective problem is presented so clearly, then after one or two hints that it doesn't have to be that bad, you can leave it at that. Try to address his wishes and offer solutions instead of just referring in a questionable way to "that's your problem in your head," I find that presumptuous.

We ourselves have fairly nice neighbors and still want to sit undisturbed on the terrace without anyone staring at the sausage on our plate. I can be open, friendly, and helpful and still want to have my domain to myself as much as possible.
Yes, it probably doesn’t work so well here, but then you can give tips on design, for example.

I can understand the OP here, everyone is different, he wants his maximum peace and help from the forum for that. If you can't provide that, okay... but don't always beat the same drum.

Light blue is the building envelope, black the plot, right? What is in the east? Building land? Playground? What may be built there? Do you want parking spaces or carport or garage? Where does the west neighbor have their terrace or recreational areas in the garden?

I would move the house as far west as possible and more to the north. Parking spaces facing the street to the south. If the neighbor is that tall, you won’t get much west sunlight anyway. With the carport etc. attached to the house, you have quite a long visual barrier to the west neighbor. I would arrange the rooms in the house differently so that the garden is connected behind the house. Why squeeze onto the tiny terrace when you have so much space? Swap the office, stairs, bathroom with the kitchen and living area. Kitchen facing the terrace. Make sure you don’t have windows parallel to the neighbor. The privacy screen you marked doesn’t help with the upper windows. Anyone who wants to look can see almost everything from above. I would rather put one further away from the boundary on the property, that one can also be higher.

Try to address his wishes and offer solutions instead of referring to "that's your problem in your head" in a dubious way, I find that presumptuous.

Here you go:

find a proper architect to create a design. Then you can go to your general contractor with it.

The expert offers possibilities that a layperson's limitations simply can't. It's also about orientation etc., not just shifting walls. And of course also about aesthetics, how to design a two-story building attractively instead of just crudely erecting walls.

referring to "that's your problem in your head," I find that presumptuous.

Since it’s simply much cheaper to solve in the head, by six figures, than on the property, the remark is just meant to be helpful. But of course one can also respect if someone wants to stick to their opinion after the remark. In another thread, someone just said today that they want KfW40 completely without the reservation of whether that is the best way for them. That is also allowed. Nobody has to orient themselves to the 11th way, my ego is dimmable ;-)

We ourselves have reasonably nice neighbors and still want to sit undisturbed on the terrace without anyone looking at the sausage on our plate.

Where neighbors are needed to look at the sausage on the plate, a dog is urgently needed :-)