Can I send emails from more than one email address or domain?

All emails in FunnelFLARE are sent using your Email Service Provider. Gmail/Office 365 will typically not allow you to send using an email address that is not the authenticated user. Thus the email should be sent from the contact manager of the recipient. 

The short answer is, no. You can only have one authenticated email service account per seat in FunnelFLARE. If you need to send from more accounts, you will have to purchase more seats.