public function scopeOrderByEventType($query, $direction = 'asc')
    {
        return $query
            ->select('events.*')
            ->leftJoin(
                'event_types',
                'events.event_type_id',
                '=',
                'event_types.id'
            )
            ->leftJoin(
                'event_type_translations',
                'event_types.id',
                '=',
                'event_type_translations.event_type_id'
            )
            ->where('event_type_translations.locale', locale())
            ->orderBy('event_type_translations.title', $direction);
    }

You won't need that complexity because your fields are not translatable but hopefully that gives you some inspiration

you don't need a scope either if you don't want to

Could be

public function order($query, array $orders = [])
    {
        if (array_key_exists('userName', $orders)) {
            $direction = $orders['userName'];

            unset($orders['userName']);

            $query->with('user')->orderBy('user.name');
        }

        return parent::order($query, $orders);
    }