Converts a JSON object into a PSObject, replacing these_property_names with ThesePropertyNames

ConvertJsonPropertiesToTitleCase.ps1

$Object = ConvertFrom-Json '{ "base_url": "https://foo.bar" }'

$Properties = foreach ($property in $Object.PSObject.Properties) {
    $newNameFragments = @($property.Name -split '_').ForEach{
        [CultureInfo]::CurrentCulture.TextInfo.ToTitleCase($_)
    }

    # Select-Object property rename via selector hashtable; Name is the new name, Expression is the original name
    @{ Name = -join $newNameFragments; Expression = $property.Name }
}

$Object | Select-Object -Property $Properties