I am the author of Helvetia, feel free to ask me anything!
I haven't realized that typing the above comment. :D
EDIT: Adding this since I found it after asking https://en.wikipedia.org/wiki/Talk%3AHell,_Norway
Answer seems to be "probably not"
https://wiki.osdev.org/Inline_Assembly
The power of this is that the compiler did the work of connecting variables from the two environments so we didn't have to write glue code.
There have been countless times where I've thought to myself "this would be trivial in another language". Can you write some kind of general purpose "embedder" that lets us use Javascript in C++, or PHP in Javascript even (PHP is simultaneously the best and worst language I've ever used). Maybe Swift or Kotlin or even Rust in Javascript. Stuff like that?