Floor plan, ideas for spatial separation within the kitchen

I would personally plan a laundry chute and a central vacuum system (at least the pipes & sockets, the "vacuum" can come later). Good idea with the shower on the ground floor for later. But don't forget to make the door to the bathroom wider and the shower "flush with the floor".

[*]Possibility of potential separation of the ground floor from the upper floor

To add once more: for a division into two apartments, the study room would be too small to be used as a bedroom again.
So, a fully-fledged apartment would have to be designed differently (possibly plan the living space so that a partition wall can be installed if needed to create a bedroom)

But honestly, when the time comes in xx years, then sell and build smaller

I would personally plan a laundry chute

For what? ... ...

Well, to then go and get the laundry from the basement when you want to wash it in the utility room on the upper floor.

That's why the central vacuum, to get the laundry back up again.

Do your children like to bathe? Or would you like to reduce the children's bathing?

The only bathroom with a bathtub is accessible through the bedroom. In addition, it is not even 10 sqm. Personally, I wouldn't find that very good. My kids bathe (unfortunately) almost daily – okay, given the size, it doesn't require much water yet. I can’t imagine that when they’re older, they will always have to tiptoe through my bedroom first before blocking the tub/bathroom for hours.

Otherwise, I also found the two home offices excessive – however, you have already written that you need both rooms. However, the suggestions from ypg regarding working with a laptop (#14) and from milkie (#19) regarding multi-use of a room were quite interesting – I will also try to incorporate them into our planning.