The structural and electronic properties of ${\mathrm{KTaO}}_{3}$/${\mathrm{KZnF}}_{3}$ and ${\mathrm{KTaO}}_{3}$/${\mathrm{KNiF}}_{3}$ oxyfluoride superlattices are studied from first-principles density functional theory calculations. We highlight, that beyond a critical layer thickness, these systems exhibit an insulator to metal transition that gives rise to the appearance of two-dimensional electron and hole gas, confined both, due the band alignment, within the oxide layer. The origin of the insulator to metal transition is related to the polar discontinuity at the interfaces. The behavior is discussed in terms of a simple electrostatic model and compared to that of the prototypical ${\mathrm{LaAlO}}_{3}$/${\mathrm{SrTiO}}_{3}$ oxide system. The magnetic properties ${\mathrm{KTaO}}_{3}$/${\mathrm{KNiF}}_{3}$ superlattices are further discussed, revealing a sizable Rashba-type spin splitting at these interfaces, much larger than in similar oxide/oxide systems.