Don’t really think this is what the OP is asking but… a gravelised CX bike, i.e. with slightly fatter tyres and more gears (or not! I would singlespeed mine if I could be bothered and thought I was robust enough…).
You will end up actively seeking out the muddiest trails, dog walking trails around the outskirts of villages become your playground, you’ll go sideways around every corner, you’ll pedal your tits off and tarmac linking sections are just an opportunity for a breather.
I actively plan routes for the winter now, typically with lots of singletrack that’s choked with nettles in the summer. I avoid anything crazy hilly right enough, that’s not what it’s really about for me in winter