OK, what part of your task do you have a problem with?

Do you want to always start in %userprofile%\desktop, no matter what local directory is set for that site in the INI file?
Use LocalDirectory raw site settings:
https://winscp.net/eng/docs/rawsettings#localdirectory

See also https://winscp.net/eng/docs/commandline#session

I want to implement a 1 click solution - user clicks on a BAT file which invokes Winscp and automatically connects to a site that exists in winscp.ini and automatically sets the local direcotory to: %userprofile%\desktop.

I've tried for hours and searched here.
Help appreciated.