Mandatory requirement for "effective date"

No, there is no mandatory requirement to mention "effective date" in any specific forms or procedures along with the form number and revision. ISO 9001:2015 clause 7.5.2 mentions date as an example, not a mandatory requirement.

Although it is not mandatory it is commonly used in procedures and work instructions, not so common in forms.

The following material will provide you more information about document control:

• How to structure quality management system documentation - https://advisera.com/9001academy/knowledgebase/how-to-structure-quality-management-system-documentation/
• New approach to document and record control in ISO 9001:2015 - https://advisera.com/9001academy/blog/2015/06/30/new-approach-to-document-and-record-control-in-iso-90012015/
• Some tips to make Document Control more useful for your QMS - https://advisera.com/9001academy/blog/2014/05/20/tips-make-document-control-useful-qms/
• Free online training ISO 9001:2015 Foundations Course - https://advisera.com/training/iso-9001-foundations-course/
• Book - Managing ISO Documentation: A Plain English Guide - https://advisera.com/books/managing-iso-documentation-plain-english-guide/