Season pork with Adobo. In blender, add annatto paste, onion, garlic, Naranja Agria, lemon juice, vinegar, Sazón, cumin, smoked paprika and cinnamon. Blend until well combined, about 30 seconds. Rub pork all over with marinade; cover and refrigerate at least 4 hours, or up to 24 hours.
Line 4-qt. slow cooker with banana leaves. Place marinated pork shoulder in slow cooker; top pork with any remaining marinade. Cover pork with banana leaf. Cook on LOW until pork is tender and shreds easily with fork, about 8 hours.
Mean while, in small bowl, mix together vinegar, lime juice, sugar, and habanero pepper until sugar is dissolved. Stir in onions; cover and marinate in refrigerator at least 4 hours.
Transfer pork to cutting board; shred pork. To serve, scoop shredded pork into warmed corn tortillas; top with pickled onions and cilantro.