Before diving into the tools, let’s address the keyword: offline . In an era of cloud saves and web-based cheat engines, why would you want a desktop application?
Some modern RPG Maker games have "integrity checks" that detect altered saves.
for MZ. Some universal tools can even handle save files from other engines like Advanced Visual Editors:
For the older generation of games (think Ib , Mad Father , The Witch’s House ), you need a Ruby-specific editor.