This would take a lot of time to do =/ but I'll try if I can do it somehow faster. However, I wonder which game engine are you using that doesn't give you support to slice spritesheets? This is kinda the standard
That would be very helpful. It would allow one-click bulk importing of the all the tile-sets at once. With the built-in sprite sheet cutter, the process involves manually configuring, importing and verifying each set.