When I import a csv that contain the character "ñ", it appears as �

[aanciones]

Could yo help me. This is my code:

[aaa2000]

Maybe, you could try

$encodingFrom = 'ISO-8859-1';
$encodingTo = 'UTF8';
$filepath = '/tmp/test.csv';

$reader = new CsvReader(new \SplFileObject('php://filter/read=convert.iconv.'. $encodingFrom .'%2F'. $encodingTo.'/resource='.$filepath));