Got it going. Syntax error. Correct script is as below:
WinSCP.com /command ^
"option batch abort" ^
"option confirm off" ^
"open sftp://genesis@202.135.116.217/ -hostkey=""ssh-rsa 1024 4e:3a:34:f9:7e:da:f4:7d:2b:7e:f1:bb:5d:c8:c9:2d"" -
privatekey=""D:\New Private key.ppk"" " ^
"put D:\Dest\Test.txt /from-post/Test.txt" ^
"pause"
WinSCP.com /command ^
"option batch abort" ^
"option confirm off" ^
"open sftp://genesis@202.135.116.217/ -hostkey=""ssh-rsa 1024 4e:3a:34:f9:7e:da:f4:7d:2b:7e:f1:bb:5d:c8:c9:2d"" -
privatekey=""D:\New Private key.ppk"" " ^
"put D:\Dest\Test.txt /from-post/Test.txt" ^
"pause"