Tool to easily create nine-sliced sprites

If you want to export large sprites from Photoshop or other image app, that will be nine-sliced in another app such as Unity, you may find the Nine-Slicer app useful.
https://store.steampowered.com/app/839180/NineSlicer/?beta=0
It essentially lets you visually set your optimal slicing values to optimize your sprite sizes, keeping your atlas sizes as small as possible.