front.entry.index.initialize:
 - [onFormFrontEntryInit, NORMAL]
front.mypage.change.index.initialize:
 - [onFormFrontMypageChangeInit, NORMAL]
admin.customer.edit.index.initialize:
 - [onFormAdminCustomerEditInit, NORMAL]

<?php
namespace Plugin\MyCustomEntry;
use Eccube\Event\EventArgs;
class Event
{
    private $app;

    public function __construct($app)
    {
        $this->app = $app;
    }
    /**
     * 新規会員登録ページの必須項目を除外
     * @param EventArgs $event
     */
    public function onFormFrontEntryInit(EventArgs $event)
    {
        $builder = $event->getArgument('builder');
        $builder->add('tel', 'tel', array( 'required' => false ));
        $builder->add('zip', 'zip', array( 'required' => false ));
        $builder->add('address', 'address', array( 'required' => false ));
    }

    /**
     * マイページ/会員情報編集ページの必須項目を除外
     * @param EventArgs $event
     */
    public function onFormFrontMypageChangeInit(EventArgs $event)
    {
        $builder = $event->getArgument('builder');
        $builder->add('tel', 'tel', array( 'required' => false ));
        $builder->add('zip', 'zip', array( 'required' => false ));
        $builder->add('address', 'address', array( 'required' => false ));
    }

    /**
     * 管理ページの会員登録・編集ページの必須項目を除外
     * @param EventArgs $event
     */
    public function onFormAdminCustomerEditInit(EventArgs $event)
    {
        $builder = $event->getArgument('builder');
        $builder->add('tel', 'tel', array( 'required' => false ));
        $builder->add('zip', 'zip', array( 'required' => false ));
        $builder->add('address', 'address', array( 'required' => false ));
    }
}