Different skin for different players

For example player A will see that player B have a superman skin, but player C will see that player B have a Batman skin, how to do this by code? Thanks

PHP:

$pk = new PlayerListPacket();
$pk->type = PlayerListPacket::TYPE_ADD;
$pk->entries[] = [$playerB->getUniqueId(), $playerB->getId(), $playerB->getDisplayName(), $isSkinSlim, $skinData];

$playerA->dataPacket($pk);
//change skin
$pk->entries[] = [$playerB->getUniqueId(), $playerB->getId(), $playerB->getDisplayName(), $isSkinSlim, $skinData];

$playerC->dataPacket($pk);