Talend Open Studio for Data Integration provides a group of Excel components that can be used to integrate with Excel file, such as tFileInputExcel, tFileOutputExcel etc. tFileOutputExcel is used to write data into a Excel file, please refer to:
Have you tried to check the 'write excel2007 file format(xlsx) option on tFileOutputExcel component? If it does not work, you can use a custom component tFileExcelSheetOutput developed and shared by jlolling on Talend Exchange, this component supports XLSM format. Here is a KB tutorial about how to install a custom commponet into Talend Studio.