When you publish a workspace using a database or web connection, you will be asked if you want to publish or update the server connection as well.

Thanks for tips @david_r​ 

but that only upplouds my connection.

• i want to be able to change parameters on DB connections on server and have it sync to my desktop
• i want to be able to share connections with other users and have it sync to their machines
• i want to be able to use connections used by other users when i download workspace from FME server

Shared folder for .data and public Key files is not either what i'm after. It's a sync between users but not a sync to FME server... say i want to change password to connection. i have to do it on at least two places

I understand, unfortunately I do not know of any such possibility.