If you create identities that correspond to the addresses to which all these messages are sent to, then yes, you can do that.
For that, you need to do the following:
I. In Aquamail, choose the option that offers sending from the identity to which messages was sent. (This is description, I don't remember what exactly it is called. You can search for it.)
2. To make sure those messages would be accepted by Gmail servers:
You can do it in to different ways (maybe more):
- Send everything through the main Gmail account
For this scenario, you'd need to create aliases (identities) in that "main" Gmail account.
It is not that difficult. For details, look at the sticky topics at the top of this forum: https://www.aqua-mail.com/forum/index.php?board=2.0
In this case, you will have all Sent messages in your "main" Gmail account.
- Send all messages through their individual accounts
For this, you'd need to specify a different SMTP server for each of the identities (actually the server will be the same, but the username/password should correspond to the individual Gmail accounts). In this case, you don't need to create any aliases in your Gmail accounts.
In this case, you can have all "Sent" messages in their respective Gmail accounts, or you can have two copies: one in the respective Gmail account, and the other one in the "main" Gmail account. For the latter, you'd need to enable "Store a copy to 'Sent'" in Aquamail settings for this "main" Gmail account.
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