Strange that there is not an offset feature in Blender like this addon does. And it looks so simple that you maybe think it’s not worth it to install such a small feature. But things look different when you look closer. I took a peek into the code and I knew it was not that simple as I thought at first. You will want to have this feature in Blender per default. And a good thing: the Offset Edges addon doesn’t occupy space in the N-panel when you are in object mode.
It happens sometime you want to do something fairly simple, but you have to work your way around it. Offset Edges is such an example. In the screenshot you see what once was a curve. (Extra objects, Curve profile, Flower). Then I converted that into Mesh. Normally the is not a direct way, even with curves to Offset Edges like this. Since the addon doesn’t bother you when you don’t need it, why you don’t want to have it in your toolset?
Download and installation
It seems the original author of the Edges Offset addon is not active on Github anymore. But luckily the user Ramboblender on blenderartists.org, it seems, made an update a few months ago. It is still working. If not, you might need to scroll a bit further down the thread. Right click on the link, save target as .py file. Then in Blender: Edit > Preferences > Addons and navigate to the download and press install.
How to use the Offset Edges addon?
Its quite simple. For example, start with a plane and go in Edit mode. Select the face and press Ctrl+E, look at the bottom of the menu and you see Offset Edges. It seems it doesn’t matter if you are in vertex-, edge- or face-select. Pretty sure this has loads of use-cases.