It seems final result of both of these tools are same. Is there any particular purpose for Drive Sketch tool?
Derived sketch is to create a copy of existing sketch (similar to what to get with convert entities) and you can move it around and position differently (unlike convert entities). Any changes made to original sketch would be reflected to the derived sketch.
Whereas Mirror icon you've up there is to do feature/body mirror and no where related to derived sketch.
I couldn’t understand this.
In addition to what you say I found that sketch created by Drive Sketch tool can be made it independent if you want. That means link with the original sketch can be broken. This is not possible with image created by mirror tool.
This is the icon for sketch mirror.
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