Let's assume a scenario where you have personal github account and another account for git at work. And you clone all your work related repositories at D:\MyWorkFolder.

In such scenarios, create a dedicated git for work as .gitconfig_work at the same location where your .gitconfig located. Generally it is located at %USERPROFILE% folder in windows. Update your .gitconfig to have similar to this. includeIf statement will redirect to .gitconfig_work for all repos closed in your work folder.

    [user]
      name = Smart User
      email = user@personal.com
    [includeIf "gitdir/i:D:/MyWorkFolder/"]
      path = ~/.gitconfig_work

Sample .gitconfig content

    [filter "lfs"]
      clean = git-lfs clean -- %f
      smudge = git-lfs smudge -- %f
      process = git-lfs filter-process
      required = true
    [user]
      name = Bipul Raman
      email = 1234567890@users.noreply.github.com
    [includeIf "gitdir/i:D:/OfficeRepos/"]
      path = ~/.gitconfig_work

Sample .gitconfig_work content

    [filter "lfs"]
      clean = git-lfs clean -- %f
      smudge = git-lfs smudge -- %f
      process = git-lfs filter-process
      required = true
    [user]
      name = Bipul Raman (Office)
      email = office@bipul.in