FF6 style GBA adult Rydia

Just having some jokes man. Use whatever program you are most comfortable with. As long as you keep your palettes in order you'll be fine, and be sure to keep backups if you are altering any files you particularly care about.

Also I do like the one on the right more, but it does look a bit off perspective wise. If you're really committed to using that one you could just try to smoosh it in a few pixels and it will probably look better. That being said the one on the left looks good too.