Hi Shailesh,
Thanks for your interest in Syncfusion products.
We have explicitly removed desktop ReportDesigner application from version 4.1.0.16 and if you want to download desktop ReportDesigner, then we can get the ReportDesigner exe file from the below link from installed ReportServer.
https://<<server name>>/ReportDesigner/Syncfusionreportdesigner.exe
Regards,
Vinoth S.