Hi,
Please let me confirm with you first, do you want to set the outgoing email as the default sender, and other users do not need to choose it? If so, there is currently no way to achieve this.
As a workaround, create a new email and save it as an outlook template after changing the “from”, and use this template when sending emails.
Create an email message template. File > Save As> In the Save as type list, need select .msg.
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