kos-language-server VS dockerfile-language-server

As to language differences kRPC relies other programing languages which means you need to set up whatever stuff is required to actually those languages. A result of this is that things that are native features of kOS stuff like vector operations, PID controllers, and cooked steering are things you are going to have to implement your self. On the other hand beyond a language server that IIRC only supports vsCode and 2 other editors there are syntax highlighting files found in the side panel under the "Editor Tools" link that are old kOS doesn't have much editor support compared to other languages. And lastly the other big thing kOS is generally considered to lack is a way to resolve things after an error happens if a script errors it crashes fully with no way for you to catch and respond to the issue which means you need to check for things like divide by zero errors before places where they can happen if you want to avoid crashing. There are a few other oddities to how kerboScript works but those add just that slight flavor of jank that makes it feel like kOS is indeed the rocket guidance system that kerbals would have developed.

Unless emacs is able to use one of the already built syntax files found linked in the side panel on the right of this subbredit under "Editor Tools" or is able to use the language server built for VScode then I am not aware of any such tools.

Also, some of the LS implementations require Node to run the daemon (i.e. Docker LS).