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 G Suite offers the same functionalities as the private version of Gmail.
To find more information about G Suite in general click here.