If you think about it, Godot fits very well and is very, very cross-platform. It brings somewhat more but you can strip it down to only the necessary, throwing away the 3D stuff and keeping only what you use. It includes a scripting language and the GUI stuff. Someone could actually build a specific solution with it!
https://docs.godotengine.org/en/stable/engine_details/develo...
https://docs.godotengine.org/en/stable/tutorials/editor/usin...