Mix cumin, coriander, cilantro, garlic herb seasoning, Italian seasoning, cayenne pepper, and fennel in a bowl to make seasoning mixture. Rub 2/3 of the seasoning mixture over pork loin.
Heat 1 tablespoon oil in a stovetop pressure cooker over medium heat. Add pork loin; cook until browned, about 3 minutes per side. Transfer to a plate.
Pour 2 cups chicken broth and rose wine into the pressure cooker. Bring to a boil, scraping the bottom to loosen browned bits. Return pork loin to the cooker. Cover and bring to high pressure according to manufacturer's instructions. Reduce heat to low and cook, about 1 hour.
Release pressure carefully according to manufacturer's instructions. Transfer pork loin to a cutting board; let cool.
Set oven rack about 6 inches from the heat source and preheat the oven's broiler. Line a baking sheet with aluminum foil; place chile peppers on top.
Roast until peppers are blackened and blistered, 5 to 8 minutes. Place in a bowl and seal with plastic wrap. Allow peppers to cool, about 20 minutes. Stem, peel, and seed the peppers; dice.
Heat a dry skillet over medium-high heat. Add some tomatillos in a single layer; cook, turning occasionally, until softened and skins are blistered, 5 to 10 minutes. Repeat with remaining tomatillos. Dice tomatillos.
Combine 1/2 of the tomatillos and 1/2 of the roasted peppers in a food processor; puree until smooth.
Heat remaining 1 tablespoon oil in a small skillet. Add onion; cook and stir until softened, about 3 minutes. Add garlic; cook until fragrant, about 1 minute. Remove from heat.
Shred pork loin with 2 forks; add to the pressure cooker. Stir in remaining 3 cups chicken broth, diced peppers, diced tomatillos, tomatillo-pepper puree, onion mixture, and diced tomatoes. Add remaining seasoning mixture, salt, and pepper. Bring to a boil; cover.
Bring to high pressure according to manufacturer's instructions. Reduce heat and cook for 20 minutes. Release pressure according to manufacturer's instructions.
Mix potato starch and cold water in a small bowl until dissolved. Pour into the pressure cooker, stirring well to incorporate thoroughly.