After Patching with :
https://github.com/ezsystems/ezpublish-legacy/commit/bd8a1684d2c9f83d9a0940800f6c91cc817d4756

Adding $base . "data_object_relation_list" . $contentObjectAttribute->attribute( "id" ) in template solved store order issue in Relation List.

When create or edit object in ezobjectrelationlist, object's attributes are not stored with post values.
Objects are stored empty.

Method validateObjectAttributeHTTPInput() does not work cause this POST attribut return instantly eZInputValidator::STATE_ACCEPTED.

Method validateObjectAttributeHTTPInput() will build $content with key temp containing post values for all objects modified

Solved with : https://github.com/ezsystems/ezpublish-legacy/pull/887