下面是对我有用的代码片段：

$language = 'en-DE'
$null = New-WinUserLanguageList $language
$list = Get-WinUserLanguageList
$wrong = $list | where {$_.LanguageTag -ne $language}
foreach($w in $wrong){$list.Remove($w)}
Set-WinUserLanguageList $list -Force -wa 0

您需要注销/登录才能查看结果。