Honestly sounds like a disaster waiting to wrap itself around a tree to me. If all 4 tyres are the same (all summer/all winter) you'd be much better than 2 each. Fronts grip, rear's do not, and when you hit the brakes the rears might lock or let go at any time.
Do not want.
0% credit card / early Xmas present from the 'rents (assuming you're not in your 80s :rasp
and get 4 tyres, or don't bother.
Driving in winter on "summer" tyres has never been a problem for me, in the Scoob or any previous hot hatch/cold yoof mobile. Just use your brain and drive sensibly for the conditions. Nothing will save you from black ice anyway...
Not trying to teach you to suck eggs, but it really just does not sound like a good idea at all.