Use the "reply-to" option if you want your recipients to reply to a different email address than the one you sent your mail merge.
Set a different reply-to email address
Open your spreadsheet. From the Add-ons menu, select Yet Another Mail Merge (YAMM). Click Start Mail Merge.
Select the draft you prepared for your mail merge and then click '+ Alias, filters, personalized attachments'.
In our example, we unchecked the tracking option.
In the Reply-to address field, enter a different email address (the one you want to receive your recipients' responses). Click Back.
The "reply-to" email address appears in the email.
Set multiple different reply-to email addresses
Add different email addresses in the Reply-to address field separated with a comma and space.
When the recipients click Reply, they will reply to all the specified "reply-to" addresses.