I am aware that one can sign out of Gmail web sessions through its main interface, and one can remove account access for devices through Google Account > Security > Your Devices. The latter only allows you to remove access to mobile devices, not computers (see image below).
So, how can I remotely log out or revoke access of Google Backup and Sync which is installed on computers and syncing with your Google Accounts, as well as Google Chrome?
I think this is a critical security issue, especially for freelancers who worked on-site and lost their access to whatever computers they were working on. Sometimes people missed the opportunity to do it in time, due to the nature of the type of the job; or simply forgot it and only think of it couple days/weeks/months later.
Best Answer
You can only achieve this by changing your password.
Apart from the browser you enable two-step verification on, enabling two-step verification will pause the sync on all Chrome browsers you're signed in to, and sign you out of all web sessions, but it won't sign you out of Backup and Sync.
If you go to Gmail, click on "Details" on the bottom right (under "Last account activity") then click "Sign out of all other Gmail web sessions", you will only be signed out of Google websites on browsers that aren't signed in to Chrome. So, if you're signed in to Chrome on another computer and you do that, Chrome will re-log you back in to the Google websites.