How to merge WYSIWYG fields from separate nodes
Welcome to Drupal Answers. You can use views module with simplenews to achieve above functionality.

Please find simplenews features below.


Sending nodes as newsletters to subscribers
Multiple newsletter categories with separate settings
Per category and multi-signup Blocks and Pages
Subscriber management including mass-subscription and export
Optional E-mail confirmations for anonymous users
Customizable newsletter templates
Support for HTML (including text alternative) newsletter when used in combination with a supported mail system module
Views and Rules integration
Support for multi-language newsletters