Preheat the oven to 375 degrees . Line 2 baking sheets with parchment. Separate 2 sheets of the crescent dough. On a lightly floured surface, roll out each sheet into a 7-by-9-inch rectangle and trim the edges. Using a sharp knife or a pizza cutter, cut 1-inch strips from the long side and cut each strip crosswise into thirds.
Cut each frank lengthwise about three-quarters of the way through and stuff with about 1 tsp. sauerkraut. Press the franks together and roll up each in a strip of the dough, so the seam is on the bottom and the sauerkraut is on the top; transfer the wrapped franks to the prepared baking sheets. Sprinkle the top of each frank with a pinch of paprika and bake until light golden, about 15 minutes.
Combine the mustard ingredients, as indicated below, in small serving bowls. Serve the pigs in blankets hot with the flavored mustards.