Similiar program like Wintousb for linux?

[JohnGantz]

Hey, currently I'm trying to make portable windows with external hdd reason is due to work and I don't want to dual boot windows either. I know in windows there is an app called wintousb to make this a bit easier so is there a similar app on linux too? Because windows can't be installed through a usb I'm a bit at a loss at what to do here

Solitaired