Just to let you know, the Pokemon Trainer's Final Smash is compatible with ASH, so you should be able to easily edit that Final Smash texture file.
Of course, before working on the Final Smash, extract the texture parts for all three of the Trainer's Pokemon, and place the folders in a separate directory. Next, extract the Final Smash texture and run The GIMP or Photoshop. Replace each texture part that the Final Smash texture contains, but do keep in mind that Ivysaur's Grass texture part requires an indexed palette.
By the way, there's no Emerald Texture version of this Final Smash.
Okay, thanks. How exactly do I index Ivysaur's grass in GIMP?