VMware Fusion only allows you to send a “Print Scrn” key to a VM, but that takes a screenshot of the whole screen.
Alt+Print Scrn gets you a screenshot of the current Window, which is what I use most often.
A few things you might have tried, but cannot use:
- Though a MacBook Air does not have F13 and F14, so you cannot map those keys.
- The native Mac keyboard screenshot shortcuts will not get your Print Scrn in the VM.
- You cannot use the BootCamp shortcuts either.
So have to map key combinations that you probably will not use under Windows.