modules/setting/models/Setting.php
public function getByCategories()
    {
        $data = [
            'categories' => $this->getCategories(),
            'settings' => [],
        ];

        foreach ($data['categories'] as $key => $category) {
            $model = self::find()
                ->where(['category' => $category])
                ->indexBy('id')
                ->all();
            $data['settings'][$category] = $model;
        }

        return $data;
    }
public function getByCategories()
    {
        $data = [
            'categories' => $this->getCategories(),
            'settings' => [],
        ];

        foreach ($data['categories'] as $key => $category) {
            $model = self::find()
                ->where(['category' => $category])
                ->indexBy('id')
                ->all();
            $data['settings'][$category] = $model;
        }

        return $data;
    }
Returns settings grouped by categories
@return array