Add peaches, habanero peppers, lime juice and zest, apple cider vinegar, apple juice, honey, garlic powder, sea salt, and black pepper to a blender and pulse until smooth and uniform. Small chunks are ok.
Transfer mixture to a small saucepan. Bring to a boil then reduce heat and simmer for five minutes. Remove from heat and cool to room temperature. Reserve ½ cup of sauce for finishing the skewers.
Meanwhile, cut pork tenderloin into two-inch cubes. Add to cooled peach habanero sauce and marinate for at least 30 minutes. While the pork marinates, cut onion, pepper, and peach into two-inch pieces.
Carefully thread pepper, onion, pork, and peach pieces onto metal skewers, alternating the order. (If your skin is sensitive to capsaicin, wear gloves for this step to avoid irritation from the pepper in the sauce.) Prepare grill for direct heat at about 400 degrees.
Place skewers diagonally across grill grates and cook for 10-15 minutes total, turning during the cook time to ensure all sides cook evenly. Pork is done when internal temperature reaches 145 degrees farenheit. Let skewers rest for three minutes before enoying. Brush a bit more sauce on each skewer as it cooks or after cooking while the skewers rest.