For anyone wondering - the developer is actively working on the plugin (e.g. he fixed the issue with discard that I reported in less than a day). It has no real autocompletion or go to definition right now, but you can add it yourself!
You can install <https://plugins.jetbrains.com/plugin/10209-lsp-support> and make it use <https://github.com/PMunch/nimlsp> (provided you installed it via nimble) with settings:
