Mirroring files which exist on one side only

[Centaur417]

Good day
On my laptop top I do have part of a server directory with originally hundred of files.
While I'm travelling (off line) I may work on some files; which I want to sync with the server after my return
During my absence colleagues may have worked on the same file.

If I do a TWO WAY; I get the complete server directory on my laptop; which I don't want.
If I do a MIRROR; I may overwrite the other file (server or laptop)

Have played around with Customised Sync.; end result subject to settings one of the files
gets overwritten; all though "conflict setting" was UNRESOLVED.

Any advice would be very welcome,