How do I blur/soften/apply transparency just to edges?

I am on Xara Photo & Graphic Designer 2013.

I have a headshot that I can cut out of a larger photo using the freehand tool to trace the edges and then subtract the background that I want cropped out.

Now, I'm trying to figure out how I can apply some kind of transparency to the edges to soften them up a bit so they aren't so stark and will overlay nicely over my site background once the image is uploaded.

Is there a way to do this?

Thank you for your help. :)

Feather tool.
On the top tool bar

Feather! THAT'S the term I was looking for. Thank you! I'll go try that out and let you know how it goes. :)

Worked like a charm. Thanks again!