Is installing windows in the brick cladding complex?

We are currently planning the exterior walls with clinker-air-insulation-Poroton. My wife would like deep interior window sills (to sit on), so it would make sense to position the windows as far to the outside as possible (i.e., flush with the clinker exterior wall). The construction supervisor strongly advises against this; the windows should be installed in the Poroton wall, as anything else would cause problems. Now it is clear that everything is possible if you really want it. But how difficult / unusual / expensive / error-prone would it be to position the windows toward the outside? Has anyone of you done this? If yes: how and with what experience?

We are currently planning the exterior walls with clinker-ventilated-air-insulated-Poroton. My wife would like deep interior windowsills (to sit on), so it would make sense to place the windows as far outside as possible (i.e. flush with the clinker exterior wall).

The window reveal should therefore bridge and break through the insulation layer ... yes, that sounds difficult ... but this is not uncommon in luxury apartment construction ... maybe Schöck has a product for this.