So, i was watching a gameplay of the game on youtube and the guy (MunchingOrange) put in the game a different sprite for his main character and i wanted to change the one in my game too. Then i searched for one of Valerie (the fairy gym leader of xy) and i find this one but i couldn’t edit it myself. Can someone please make this to fit in the game? Or if any of you have a custome sprite you could pass me a picture? (btw, sorry for my engish, disadvantages of being mexican lol)
I came here right after MO’s video as well, and saw this post, was searching the internet for editing the sprite, but couldn’t find a good tutorial anywhere, hope someone helps us!
You can use free programs like GIMP, Paint.NET, and Aseprite (old version) for spriting.
Pretty simple steps, open the original sprite file you want to edit from the game in the program, then open the sprite you want to have edited there, copy the matching character sprites to the original file and place on top of it, once you have them on the correct order, delete the original sprite layer, save it, and you have your sprite ready.
IT WORKS!!! Thank you so much 
Add Krita to that too, at least for free software recommendations.