Send-as and Send-on-behalf of for groups in Outlook

While it's great that Microsoft added support to "Send-As" a group in Outlook, we noticed that this feature is NOT available on small mobile devices like the iPhone using either the Outlook mobile app for iOS & Android or the phone's web browser (e.g. Safari).  From their computers, our employees can use the SendAs feature to send emails from distribution groups when using the Outlook client or by going to outlook.office365.com in a web browser (Chrome, Edge, etc.), but this same functionality is not available from their iPhone or Android phones.  The Outlook mobile app and Outlook on the web in the mobile app's browser do not provide a way to add the "FROM" address, so there is no way to switch the sender to an email group, which means that we have to create additional otherwise unnecessary Shared Mailboxes for each of these groups and use Send-As from the Shared Mailboxes.  Please add this DL Send-As functionality to the Outlook mobile app.