I rather wonder: How expensive and complicated will that be? Credibility is another matter (but I am just an amateur). Why not stick clinker slips directly and stay within the building envelope?
I think you are getting carried away with something there. The additional thermal insulation is generally tolerated, but with a new building this approach is usually not taken. If you still intend to do so, however, that is not a problem, the base slab is not considered as an external dimension.
I am by no means an expert... with us, the clinker was not placed directly on the floor slab, but on a ring that was separated from the floor slab by about 10 cm of rigid foam.