Yes, you can use an email alias or secondary email account to send Sequences, as long as you have a cloud-based email inbox using G Suite (formerly known as Google Apps) or Office 365 and you are sending your email from Gmail or desktop Outlook. This functionality is not currently supported when sending Sequences from within the HubSpot CRM.
This will not work if your email address is hosted by Outlook Exchange. Check out your Manage Users page to ensure your user's email address is the address you use in either G Suite or Outlook 365.
An email alias is an alternate address that points to a user's existing Gmail account. You can create an alias in your Gmail account and use that alias to send a sequence without issue.
A secondary account is another, unassociated email address you may have. For example, you can log into your personal Gmail account (a different account than the one paying for HubSpot Sales Pro) and send a sequence.