Bathroom planning 7.8 sqm

If the tub is only for the little children, I would leave it out. As long as children are so small that they "have to" bathe, they still fit in a laundry basket or a baby bathtub. When they are bigger, they can shower. Or the bathtub goes straight into the [Kinderbad]/[Hauptbad]/[whatever].

I see few good options to implement a bathtub and shower in the bathroom with floor-to-ceiling windows and the door position.

And,

walk-in shower variant (width 85cm, length 1m)

is not really a size for normal walkability. You definitely have to factor in partition and shower door.

I think she doesn't mean "offen" but flush with the floor without a shower tray.

If the tub is only for the little children, I would leave it out. As long as children are so small that they "have to" bathe, they also still fit in a laundry basket or a baby bathtub. If they are bigger, they can shower. Or the bathtub goes straight into the children's bathroom/main bathroom/whatever.

Habits do change, though. So it may also be that you have to take baths.

If there is no drainage planning yet that allows you to change the toilet and shower, then you can also still consider the floor-to-ceiling window. However, I see the problem in the position of the door. Is it possible to place the bed on the other side in the bedroom? Then you would have a room with four free corners. Or how about using a combined shower tub in the children's bathroom?

Or how about using a combined shower tray in the children's bathroom?

I think the idea is really good and have just inquired about it.

The implementation currently looks like this.