​@soner Prior to 21r1, there were two types of Excel plugins - a template driven design: 

https://docs.ifs.com/techdocs/25r1/060_development/025_operational_reporting/190_using_report_plugins/040_excel_plugin/

and a simple plugin with limited configuration: 

https://docs.ifs.com/techdocs/25r1/060_development/025_operational_reporting/190_using_report_plugins/140_simple_excel_plugin/

If you are on Apps10, you should be able to create Excel templates and upload them to Solution Manager/Operational Reporting/Report Layout Templates.

https://docs.ifs.com/techdocs/Foundation1/050_development/025_operational_reporting/190_using_report_plugins/040_excel_plugin/work_with_templates.htm