In a 12-inch skillet over medium, heat the oil until shimmering. Add the poblano chili, corn, scallions whites, and 1/2 tsp salt and pepper. Cook, stirring occasionally, until the vegetables begin to soften, about 5 minutes. Add the cumin and cook, stirring, until fragrant, about 30 seconds.
Stir in the quinoa followed by the broth, then bring to a simmer over medium-high. Cover, reduce to low and cook, stirring and adjusting heat as needed to maintain a simmer, until the quinoa is tender and the liquid is almost fully absorbed, 15-20 minutes.
Off heat, add half the feta cheese and half the cilantro, then stir until the cheese has melted into the quinoa mixture. Taste and season with salt and pepper. If desired, transfer to a serving dish. Sprinkle with the remaining cheese, cilantro and scallion greens. Serve with lime wedges.