Am I able to recall an email once it has been sent in a customer journey if it hasn't been opened?

@Lindsey Bell, Thanks for posting in Q&A. Based on my researching,

Message recall is available after you select Send and is available only if both you and the recipient have a Microsoft 365 or Microsoft Exchange email account in the same organization. So, for example, a message sent to or from a Hotmail, Gmail, or live.com account or account in other organization can't be recalled. 

https://support.microsoft.com/en-us/office/recall-or-replace-an-email-message-that-you-sent-35027f88-d655-4554-b4f8-6c0729a723a0

Hope the above information can help.

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