TZUtil or Windows Time Zone Utility can be used to display current time zone ID or set the system timezone to specified time zone ID, with support to disable Daylight Saving Time adjustments (if applicable) for the time zone with _dstoff suffix.
For example if you want to change the current Time Zone for the clients through GPO to W. Europe Standard Time. Save the following command as cmd file and deploy it as log on script.
tzutil /S "W. Europe Standard Time"