Cut the pork loin into uniform 1-inch cubes and place them in a medium glass mixing bowl.
In a small bowl, whisk together the gochujang paste, coconut aminos, rice vinegar, toasted sesame oil, honey, grated fresh ginger, and minced garlic until smooth.
Pour two-thirds of the marinade over the pork, tossing well to coat, and let it marinate for at least 20 minutes in the refrigerator.
While the pork marinates, slice the zucchini into thick half-moons and chop the red bell pepper into 1-inch squares.
Thread the marinated pork cubes onto skewers, alternating with the zucchini and bell pepper pieces.
Preheat a grill pan or outdoor grill to medium-high heat and lightly grease with a high-smoke point oil if necessary.
Grill the skewers for 3 to 4 minutes per side, or until the pork is cooked through and the vegetables have developed a nice char.
During the last 2 minutes of cooking, brush the remaining marinade onto the skewers for extra flavor.
Remove from heat and garnish with sea salt, black pepper, sesame seeds, and thinly sliced green onions before serving.