Parent bathroom + children's bathroom arrangements

Can you please make me a suggestion?

Children's bathroom only built with bricks below, glass above:

Thank you but the measurements are exactly the other way around in the parents' bathroom. I must have written it wrong. You would have to swap 3.1m and 3.55m. But then you are already standing very cramped between the sink and the bathtub, right?

How flexible are the window positions? Especially in the main bathroom, the shower can basically only be placed in the top right of the room due to the position of the window and the door. Both the bottom left and right are blocked by the window.

Is the window dictated by an identical window on the ground floor?

Quickly, here are 3 ideas for the children's bathroom. I have always left the main bathroom the same, I kind of like it that way.

Children's bath is also about 3.5 meters wide instead of 3.1m. Doesn't the window interfere there when showering? Can the wall also be 1.6m long? Then there would be an entrance of 80cm or is that too little? How wide should an entrance be at least?

The window in the master bathroom is not fixed. It can be changed arbitrarily. Symmetry from the outside is no longer that important to us. We have realized that we cannot have everything.

If you want, you can still try something in the main bathroom with a different window.