I don’t know if it would be possible, but if there’s some (even hacky) way to do this, it would be revolutionary and solve many of the things I have problems with in BPs.
How it would ideally work: You create a native C++ function node in the event graph like any other node, then double click it to go into the editor window. It doesn’t have to be advanced at all, just respect indentation and such. You write some native c++ code in there and press compile. If it succeeds, it now creates a BP representation of that code, exactly like an UFUNCTION() does with connectors for inputs and outputs.
With this it would be trivial make those functions that are annoying or impossible to create in BPs. Say you wanted to grab some lines from an .ini file. You would have to create a C++ project in order for that, or write a plugin that had a function that your BP could hook into. Both those solutions work but are way more intimidating for someone like me who would rather stay in BP-land for as long as possible and just dip my toes into c++ when absolutely needed.