How to move your source code from TFS VCS to TFS Git or GitHub
There's an excellent cross platform command line tool available called Git-TF. In a nutshell, it will let you clone an existing TFS managed project and initialize a local git repository. You can then hook itself to a remote Git repository (Gothub, Bitbucket etc.) and push the code along with all the commit / checkin history. I just moved one of my projects from TFS VCS to TFS Git in less than 30min in Mac running macOs.