Heat air fryer to 375°F. In large bowl, toss Brussels sprouts with 4 tablespoons oil, then paprika and ½ teaspoon salt. Air-fry Brussels sprouts in 2 batches until charred, crispy, and tender, 9 to 11 minutes.
Meanwhile, in bowl, whisk together maple syrup, sriracha, and a pinch of salt. Transfer 2 ½ tablespoons to small bowl and whisk in remaining tablespoon oil; set aside for serving.
Transfer 1 batch roasted Brussels sprouts to large bowl and toss with 2 tablespoons of remaining syrup mixture. Repeat with remaining Brussels sprouts and 2 tablespoons syrup mixture.
Transfer to platter, then drizzle with reserved maple-oil mixture and sprinkle with Aleppo pepper and scallions if desired.
