Oxygine - Cross-Platform 2D C++ game engine

Free, Open Source and Cross-platform

        Oxygine is completely free and open source (MIT license) 2D game  engine, available on GitHub. It is written in C++ and runs on MacOSX,  iOS, Android, Windows and Linux.

Pure C++

        Oxygine is written in C++. It provides easy to use API, which is  designed with "do more with less code" philosophy. It uses a managed  scenegraph system that takes care of rendering and updates, and provides  ability to extend  with custom rendering and updates.

Link ==>> Oxygine

The fact it’s based on Marmalade could mean trouble down the road, as that product will hit EOL next year.

They have plenty of time to port to either a custom base or a different one at least.

Can we get the cliff notes on what puts this apart from something like GDevelop or Godot?

Not sure but you can see the review what Oxygine can do.