What is the best way of approaching this such that I can avoid having to rebuild the forms manually - especially if I have a lot of forms.
1 Answer
If only a couple of forms then it may be simpler to just rebuild but if you want to migrate you could look at using https://github.com/fuzionnz/webform_civicrm_migrate and https://github.com/fuzionnz/webform_migrate_plus.
Both modules are under ongoing refinements - definitely backup before using.
(for more about migrating civicrm from d7 to d9 read: Moving existing CiviCRM to new Drupal instance + upgrade to Drupal 9)