Idea

You would need to use DeleteUsers to remove the players from the game, though that call does require the PlayFab IDs of the users in the game. An easy way to get the PlayFab IDs for all users created in the game would be to use the Admin/GetDataReport API method to retrieve the TitleNewUserReport and/or TitleActiveUsersReport documents for your title.

Thank you for your trying.
Is ther any way to read all player information at once?
GetDataReport Api only provides the data in certain date.
I want to get all play list.
Thank you for your trying again.

As stated in the other thread, you would need to get each day's data. Running this on a daily basis (as a regular job to grab the latest one) would allow you to always have the full set of data locally, while knowing that the authoritative version is kept safe in our service.