Another option is Sno Seal, or other beeswax-based product. I've been using Sno Seal on boots and gloves for years; in fact, I'm about to re-do my hunting boots after a long wet canoe trip.They are waterproof, but being a soft leather shell, I regularly buff with saddle soap and the water beads / runs off in the rain. Their blurb says:-
Waterproof/windproof/breathable Hipora® liner to provide protection from wind and rain. As with all leather goods, we recommend treating your gloves regularly with a leather protector such as Nikwax. This not only extends the life of your heated glove but also helps to keep the outer layer water-resistant.