For a fun irregular shape that looks kinda like a snowflake, spoon the waffle batter into the center of a four-square waffle iron.
Preheat the oven to 375°. Preheat a waffle iron to level 5 or medium-high to high.
Place the potatoes in a strainer; season with salt. Let drain for 10 minutes.
Arrange the bacon on a slotted broiler pan. Bake until crisp, about 18 minutes.
Wring or press out any excess liquid from the potatoes. Transfer to a large bowl. Whisk in the 2 beaten eggs, flour, baking powder, 2 tsp. salt, and 1 tsp. each white pepper and black pepper. Stir the sour cream, melted butter, and cheese into the batter.
Spray the waffle iron with cooking spray. Add a quarter of the batter. Cook the potato waffles until deep golden-brown, 5 to 6 minutes. Repeat for a total of 4 waffles.
Meanwhile, heat a griddle pan or large cast-iron skillet over medium-high. Spray the scallions with cooking spray; season. Cook until tender and brown at the edges, about 5 minutes; coarsely chop. Wipe out the pan; add the pat of butter. Cook the remaining 4 eggs over medium-low heat until over easy to over medium, 3 to 4 minutes.
Top each waffle with 3 crisscrossed bacon strips, the scallions, and an egg.