This script will decode TZI value from registry. Replace the bytes in the first line of the script with the TZI value in REG_BINARY format that you want to convert.

Time Zone Information.ps1

$tzi = [byte[]]@(0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00)
$bias = [System.BitConverter]::ToInt32($tzi, 0)
$standardBias = [System.BitConverter]::ToInt32($tzi, 4)
$daylightBias = [System.BitConverter]::ToInt32($tzi, 8)
$standardStart = [System.DateTime]::FromFileTime([System.BitConverter]::ToInt64($tzi, 12))
$daylightStart = [System.DateTime]::FromFileTime([System.BitConverter]::ToInt64($tzi, 20))

Write-Host "Standard bias from UTC: $bias minutes"
Write-Host "Standard offset from UTC: $standardBias minutes"
Write-Host "Daylight bias from UTC: $daylightBias minutes"
Write-Host "Standard start time: $standardStart"
Write-Host "Daylight start time: $daylightStart"