Powershell convert csv to xlsx - excel

Question

I have the below Powershell script to convert excell csv file to xlsx which work fine. I am running into a problem, when the csv file have german letters like "Ä,ü,ß", these are being replaced in xlsx file with
ü or something like this. I would like to save the file using UTF-8 when saving to xlsx
How can I save xlsx with desired encoding?
### Set input and output path
$inputCSV = "test.csv"
$outputXLSX = "output.xlsx"
### Create a new Excel Workbook with one empty sheet
$excel = New-Object -ComObject excel.application
$workbook = $excel.Workbooks.Add(1)
$worksheet = $workbook.worksheets.Item(1)
### Build the QueryTables.Add command
### QueryTables does the same as when clicking "Data » From Text" in Excel
$TxtConnector = ("TEXT;" + $inputCSV)
$Connector = $worksheet.QueryTables.add($TxtConnector,$worksheet.Range("A1"))
$query = $worksheet.QueryTables.item($Connector.name)
### Set the delimiter (, or ;) according to your regional settings
$query.TextFileOtherDelimiter = $Excel.Application.International(3)
### Set the format to delimited and text for every column
### A trick to create an array of 2s is used with the preceding comma
$query.TextFileParseType = 1
$query.TextFileColumnDataTypes = ,2 * $worksheet.Cells.Columns.Count
$query.AdjustColumnWidth = 1
### Execute & delete the import query
$query.Refresh()
$query.Delete()
### Save & close the Workbook as XLSX. Change the output extension for Excel 2003 overwrite
$excel.DisplayAlerts = $False
$Workbook.SaveAs($outputXLSX,51)
$excel.Quit()

Answer 1

string csvFileName = #"test.csv";
string excelFileName = #"output.xlsx";
string worksheetsName = "TEST";
bool firstRowIsHeader = false;
var format = new ExcelTextFormat();
format.Delimiter = ',';
format.EOL = "\r";
//format.TextQualifier = '"';
format.Encoding = new UTF8Encoding();
format.DataTypes = new eDataTypes[] { eDataTypes.Number, eDataTypes.String };
ExcelPackage.LicenseContext = LicenseContext.Commercial;
using (ExcelPackage package = new ExcelPackage(new
FileInfo(excelFileName)))
{
ExcelWorksheet worksheet =
package.Workbook.Worksheets.Add(worksheetsName);
worksheet.Cells["A1"].LoadFromText(new FileInfo(csvFileName), format, OfficeOpenXml.Table.TableStyles.Medium27, firstRowIsHeader);
package.Save();
}