Bathroom layout possible like this - distance from toilet to drainpipe

Hello everyone,
we would appreciate an assessment, as despite intensive phone inquiries, we have not been able to get an appointment with an installer before Christmas.
We are currently planning our bathroom for our new building: The question is whether this floor plan (see attached image) is technically feasible at all, regarding the distance from the toilet and sink to the soil pipe.

You have to know that below the toilet/sink is the open kitchen/dining area, so no wall. Therefore, the soil pipe cannot be directly by the toilet/sink.
The drawn blue lines roughly represent the walls under the bathroom. Is it possible to lead the drain pipe from the toilet in the floor (under or in the screed?) to one of the "blue" walls? Or is that not recommended?

Thank you for your assessment! That would really help us at the moment.

Kind regards
Johannes

What is in the ground floor where the downpipe is drawn? Is there no wall there? Is it not supposed to be realized as drawn?

What is in the ground floor where the downpipe is drawn? Is there no wall there? Shouldn't it be realized as drawn?

Thank you for the feedback. We received this suggestion from our bathroom planner. However, I had some doubts about the WC drainage (hence my post/question). There is no wall on the ground floor, but even a window :-/. It cannot be where the downpipe is drawn. That is, of course, quite amateurish by the bathroom planner. However, we quite like this arrangement and therefore the question arises whether the downpipe can also run within one of the blue walls, or if that is unrealistic.

Depends on the exact floor structure of the intermediate ceiling. But in principle, it should not be a problem if it is high enough.

It depends on the exact floor construction of the mezzanine ceiling. But basically, it should not be a problem if it is high enough.

To my knowledge, a drain is not laid crosswise, it also does not fit into the screed. I see the blue cut point at the window here, however, the pipe would also have to be vented.... I would wait until the specialists return from vacation at your place! Without the ground floor and so on, this is more than guessing here

Well, it's not great, but of course it's possible. It was done for me too. That's why I said it depends on the floor structure. but a DN10 pipe fits perfectly in 10cm insulation stapler mat + screed. There probably won't be a window on the ground floor...