NodeGraphQt is a node graph UI framework for PySide2 that can be implemented and re-purposed into applications.
https://jchanvfx.github.io/NodeGraphQt
See the basic_example.py python script from this repo.
More examples can be found in the API documentation:
https://jchanvfx.github.io/NodeGraphQt/api/html/examples/ex_overview.html#simple-example