What is a syncstatus.plist

A .plist file is just a "preference" file that contains your preferences for whatever application the preference file relates to.

Your question doesn't provide any details on why your performing these actions, but typically by moving a preference file (i.e. the .plist file) for a particular application and then relaunching that application you are starting afresh as none of your previous settings are kept.

That is, when the .plist file is not where it's supposed to be, the application will create a new one from scratch. So, moving the .plist file is often a troubleshooting step used to correct problems a user may be having with an application.

Note: Many guides recommend you trash the .plist file, but it's actually best to just move it somewhere first (e.g. to your desktop) and then to test whether that has actually resolved the problem. If it hasn't, you can then quit the application and move the original .plist file back so that you don't need to reconfigure everything again for the application.