In a large bowl, make the coleslaw by combining the green cabbage, red cabbage, and carrot.
In a small bowl or jar, whisk together the olive oil, vinegar, Dijon mustard, honey, salt, and pepper.
Pour the dressing over the cabbage mixture and toss well to coat. Let it sit for 10 - 15 minutes (or longer) to soften slightly and let the flavors develop. Taste and adjust seasoning if needed.
Preheat the oven to 425°F. Line a baking sheet with parchment paper and place a wire rack on top if you have one (this helps the bottom crisp up).
Pat the fish dry with paper towels. Season both sides with salt, pepper, paprika, and garlic powder.
Set up a breading station with three shallow bowls: Bowl 1: All-purpose flour, Bowl 2: Beaten eggs, Bowl 3: Panko breadcrumbs.
Lightly coat each fillet in flour, shaking off the excess. Dip into the egg, letting the excess drip off. Press into the panko breadcrumbs until evenly coated on all sides.
Place the breaded fish onto the prepared wire rack or directly on the lined baking sheet. Lightly spray both sides with olive oil or brush with oil.
Bake for 15 to 18 minutes, flipping the fillets halfway through baking. The fish should be golden and cooked through (internal temp should reach 145°F). Broil for the last 1 to 2 minutes if you want extra color and crispiness on top.
Remove and let rest for 2 minutes before assembling your sandwiches.