An alias is another email address you own. If you own another email address, you can send mail as that address. For example:
Another Gmail address
Yahoo, Outlook, or other non-Gmail address
Your work, school, or business domain or alias, like @yourschool.edu or firstname.lastname@example.org
First, you need to have configured an alias in Gmail. Google has a very good guide on that, which we have reported below the main steps:
In Gmail, in the top right, click Settings Settings
Click the Accounts and import or Accounts tab.
In the "Send mail as" section, click Add another email address.
Enter your name and the address you want to send from.
Click Next Step Send verification.
For school or work accounts, enter the SMTP server and the username and password on that account. The SMTP server for Gmail addresses is smtp.gmail.com, the SMTP server for Outlook addresses is smtp-mail.outlook.com.
Click Add Account.
Confirm the address: sign in to the account you added.
Open the confirmation message you got from Gmail, click the link.
Voilà! you have added an email alias
Once you have set up the email alias in Gmail, you can add the alias in Mailmeteor.
Click on Send emails from an alias
Add a new alias address by clicking on the blue button Add new alias
Fill in the input fields for the sender name and the email alias address
Make sure to copy paste the exact email address of your email alias in Mailmeteor. If there is a typo in your alias email address or if the alias is not configured in Gmail, Mailmeteor will fallback to your primary email.
Verify your email alias rate limits. If you want to use an email alias different from a Gmail account (like a Yahoo address or OVH address), your sending limit may vary depending on the provider. For example, Yahoo Mail email send limit is no more than 100 emails or recipients per hour. You may be limited if you try to send more emails than the limits.