Legs will become accustomed to the elements if you wear shorts all of the time Azz.
But if you’re not used to exposing your legs best to start in the spring/summer then they will be hardened for the winter.
In the winter I just carry a good pair of walking trousers made from a special material that maintains the heat and dries quickly for any emergencies.
But Skin is by far the best ever waterproof material.
A good map and compass and a good knowledge of map reading is the most important part of your kit, all the rest is just trimmings.
This is my usual mountain hiking kit seen here on Cross Fell (the highest part of this area of the Pennines) in shitty weather…Mind you…I did run up…
I hate the cold OGF tho in fairness my legs are usually the last to feel it, it’s mostly my arms (as I wear t-shirts) and ears!!
You can be both sweating and freezing if you go up somewhere like Pen Y Fan - you are sweating because you are continually walking uphill, and you are cold because the wind can be really bitter, especially towards the top. The weather can change very quickly too. Places like Pen Y Fan have microclimates, so you never know what you’ll get until you go there.
I don’t Pauline… tho my neighbour is always on to me about camping up there - but it’s just too cold for me! I might try it one day