Sprite Shaper
is a Unity extension to edit sprites directly in the Unity Editor
Stop wasting time opening an image editor just to apply some basic operations for textures and images. Sprite Shaper enables you to edit multiple images at once: reszie, rotate or flip an image, crop pixels or add padding pixels around it. Sprite Shaper does not use any libraries other than unity itself to do it's job, so there are no dependencies that might cause problems in the future. Also it keeps the package size extremely small (~450 KB).