You can take a look at https://github.com/j4ts, which contains some Java libs transpiled by JSweet to TS/JS. The AWT/Swing implementation is just a proof of concept, but some other libs are fully functional like awt/geom.

However, you have to be aware that the initial purpose of JSweet was not to port all Java libs to JS. JSweet allows the transpiler to be customized (with extensions) to map Java APIs to JS ones so that you don't necessarily need a JS runtime. It's all explained in the "Extending the transpiler" section of the core doc: https://github.com/cincheo/jsweet/blob/master/doc/jsweet-lan...