Preheat oven to 350°F and prepare cake pans with parchment paper and nonstick spray.
Mix sugars, flour, cocoa powder, baking soda, baking powder, and salt in a bowl.
In another bowl, whisk eggs, sour cream, milk, wine, oil, and vanilla until combined.
Combine wet and dry ingredients, mixing until just incorporated.
Pour in hot water and mix until combined.
Divide batter evenly among pans and bake for 30 minutes.
Let cakes cool in pans for 15 minutes before transferring to cooling racks.
For frosting, beat butter, sugar, salt, chocolate, and wine until smooth; frost cake layers and assemble.