I’ll try it in wood and see where I get to. Conventional rails front and back are out because of construction complexity and probably expensive. Diagonal cross rails with a bridle joint where they met are possible.
Now to the drawing board and models, observation and experimentation.
Scandinavian means simple but not simplistic. An ICF Una chair (Italian) was a good starting point – lovely back curve supporting in the right place. However it is not easy to lean forwards if you are working at your desk.
The model shows it is possible, but I’ll have to think about the way the back and seat join together – later. Here’s the first go
It looks like I can laminate the back and seat but they aren’t really strong enough.
Next time try hardwood, more laminations and a bolted wedge to join the seat and back.