PowerSlide is a brownierbend add-on for Blender that focuses on making edge loops and other supporting edge modifications easy. It provides you with easy but smart selection modifications for Primary edges and their supporting structures while keeping sharp detail on a subdivided geometry.

Andrew Smith – Powerslide Features

• Free and precise edge loop adjustment: You can now swiftly and correctly adjust supporting edges around sharp features in your model.
• Automatic loop finding: You can specify any section of an edge loop, and it will find the rest of the loop on its own.
• Multiple edge loop adjustment: Multiple edge loops can now be adjusted at once for better efficiency.
• Vertex mode support: Now you can select for more granular control by using it on vertex mode.

Preview Powerslide Addon for Blender

Image 1: Select primary edges and PowerSlide will find and adjust all supporting edges.

Image 2: Adjust multiple edge loops simultaneously.