There are several ones (selected only FOSS alternatives, excepting discontinued ones)
- Godot Engine (2D,3D)
- Redot Engine (2D,3D)
- EzEngine (3D)
- Micro Studio (online)
- GB Studio (2D)
- EasyRPG (compatible with the outdated Open RPG Maker)
- Adventure Game Studio
- OHRRPGCE (2D)
- RPG 20XX
- Blitz3D (2D and 3D, Windows only)
- Pixelbox (Html5, Java script)
- RPD JS (Online and all OS)
- RPG Wizard (2D)
- Duality (C#, OpenGL)
- G3D Innovation Engine (3D, commercial quality)
- GemRB (Portable)
Well, some of the other, even 3D don’t need big programming skills, but other need it. It depends on your skills which is the best for you. Also not the same if there are only simple scripts or if needed a knowledge in C#, C++, Html5 and others.