Floor plan and room concept family maisonette apartment: Where does what go?

Yes, the use of the DG is approved for residential purposes.

The sketch of the existing layout would be good. I would spontaneously consider, for example, whether the kitchen could be combined with the room on the left and a separate living room created as a retreat. But that belongs, as nicely asked, to the specific lifestyle...

I throw a completely different categorization into the room. Cooking, living, eating, playroom upstairs towards the loggia and the entrance as well. Downstairs the quiet rooms bedroom, 2 children's rooms and home office. Internal staircase is still missing. Does laundry washing still need to be accommodated?

Good idea, we had also considered that before. However, because of impact sound, wooden beam ceilings, we then thought that it might be quieter above all to have the bedrooms upstairs. An internal staircase does not need to be included; the washing machine should go back into the kitchen.

An internal staircase does not have to be accommodated

Why?
How do you get to the attic? The drawing is not very informative on that.

Both apartments will be accessible via the staircase. The staircase will be separated in front of the 2nd floor with its own entrance door, so that it then spatially belongs to the apartments.