What can be used in place of the buckwheat flour? …

Name: Healthy Morning Glory Muffins (GF + Vegan)
Prep time: 20 min
Cook time: 30 min
Total time: 50 min
Cuisine: Gluten-Free
Ingredients: 1/3 cup water; 1/4 cup golden flaxseed meal; 3/4 cup plant (non-dairy) milk*; 1/4 cup coconut palm sugar or maple syrup; 1/4 cup, orange juice, freshly squeezed; 1 teaspoon pure vanilla extract; 1/2 teaspoon fresh orange zest; 1 small apple, grated (1/2 cup); 1/2 (generous) cup carrot, finely grated; 1 cup GF quick cooking rolled oats; 3/4 cup buckwheat flour; 1/4 cup arrowroot starch or tapioca flour; 1/3 cup unsweetened shredded coconut; 3 teaspoons GF baking powder**; 1 teaspoon cinnamon; 1/4 teaspoon nutmeg (optional); 1/2 teaspoon fine sea salt; 1/2 cup dry organic raisins; Turbinado sugar; 8 carrot strands for rose swirls