I discovered NEOS overshoes (New England Overshoes) working on a film outside in cold, wet, snowy weather all late fall and early winter. Several members of the film crew wore NEOS and spoke highly of them.
A gusseted opening makes them easy to get on or off, and a drawstring closure snugs them up around the ankle to keep snow out. As the name implies NEOS are worn over shoes or boots. I have the insulated Voyager model and they are very warm, easy to put on or take off, and totally waterproof. I have worn them on snowy camping trips when temperatures didn’t get much higher than 20F day or night and they kept my feet nice and toasty.
The lighter-weight uninsulated Neos Villager is great for rainy or snowy days around town.
Neos Voyager Available at Amazon