Is it possible to import mails from another account into G Suite?
Yes, that’s possible and as Google reseller we often support our clients with mail migrations into G Suite. You can convince yourself by testing G Suite 30 days for free - click here to create a G Suite Trial.
In Gmail it’s also possible to recall and send mails from other accounts. In general Gmail in Google Workspace offers the same functionalities as the private version of Gmail.
To find more information about Google Workspace in general click here.