Admittedly if you had a large property with a lot of edging this method is not very efficient, but I have a smaller "city lot" and it works just fine.
Let me know how you make out.
If you look around this forum, you'll see many many calls for Ego to make a bladed edger as a separate tool or even something that may be able to be built into a trimmer.
There are some here who can use the current trimmers as edgers effectively as I'm sure you've seen lawn care professionals do in the interest of time and money. I purchased the 15" trimmer around the time it was released and was very impressed by it's power as a trimmer. In fact, it had more power than anyone would ever need in a trimmer.
The problem with the trimmer is that it's not a good edger for many homeowners posting here. I tried it as an edger and only managed to destroy some of the areas along my sidewalk. The edger has a dual line and they seem to fight each other when trying to keep the thing in a straight line. You are going to see some post saying it's fine as an edger. If it is to them, then more power to them but in my opinion it's not a good edger at all. One because it's very hard to control and two a blade creates a cleaner look than a piece of line.
I returned it.
Plenty of people use string trimmers for edging, though how well they work seems to depend on how picky the user is with the results, the skill level of the user, as well as how patient they are.
My personal experience with the 15" Ego trimmer is it works and has plenty of power, but the results depend on how much patience I have. I need to go very slow when holding it vertical to do a good job without tearing up the edge of my grass. A wheel attachment would likely help with this.
Kid Rock, after 50+ years my crack is just fine, guess it was made and grown just right!
You just turn it so the head is sideways and let the string whip the edge to cut.
I had an electric black and decker edger and stopped using it. I only use the ego trimmer for edging now.
It is actually better to use the string trimmer for edging since the string does not damage the concrete like a blade edge trimmer does.