It's much easier to get a leaf blower gutter attachment. You need to make sure that it fits your brand of leaf blower, but they're pretty easy to find. Greenworks, Black + Decker, and Ego all sell ...

You'll find people gravitate toward things that can make otherwise mundane jobs like cleaning out a gutter ... Axial Blower Attachment If you don't want to buy a dedicated leaf blower, then ...