Shadow CLJS is very easy to set up and there's a whole book's worth of documentation: https://shadow-cljs.github.io/docs/UsersGuide.html

You don't need figwheel (or any other tool) if you just want to write ClojureScript. You can get a ClojureScript browser REPL like this (mac example):

   brew install node

   npm install -g shadow-cljs

   shadow-cljs browser-repl

I get that it's going to be hard if you want to integrate stuff into an IDE that doesn't support ClojureScript. I use IntelliJ with the Cursive plugin (free version) and use `deps.edn` for dependencies since it's supported directly in Cursive.