If you have a list of guests who are associated with a group email alias, it is possible to send emails to this type of address. However, we can't guarantee deliverability, and you'll be sacrificing engagement data.
Due to the number settings that need to be modified and lack of visibility, we typically do not recommend sending to an alias. It's best practice to import your guests' email addresses directly.
If you're in a pinch, check out the settings that need to be enabled below.
Before you send an email to an alias you have to make sure "Allow External Emails" is turned on for the alias. Otherwise, the email will not be delivered. Frequently this setting is not activated because aliases are only used for internal purposes.
Using an email alias will also just show you the deliverability analytics for only one email address, not all of the associated email addresses. You will not be able to see who opened, clicked and RSVP'd from the email.