Go to your Google account and setup an app password. Might have to enable 'unsecure' access in additionele (Google think standards bases interfaces are outdated, you see). Then you can add your mail account through IMAP/SMTP, *DAV.
As with all things Google, the only winning move is not to play. Long term I'm sure they'll axe this and tell you to use their app or bust.
As with all things Google, the only winning move is not to play. Long term I'm sure they'll axe this and tell you to use their app or bust.