Hyperlinking to a Page via its Path

I have a page called en.md and another page called ko.md in a directory. Both files have custom-set permalinks, so en.md and ko.md respectively are not a part of the page URL. Regardless of this setting, to move from en.md to ko.md in normal HTML, all I would need to do is this :

<a href="ko.md">Move to File KO</a>

However, this doesn’t seem to work in Jekyll; this link sends me straight to URL .../ko.md, where there is no file (because of that permalink setting), rendering my link unusable. Is there a way to link to a specific file instead of just permalinks in Jekyll-processed HTML? Thank you!

there never will be a .md file as they get changed to html (assuming they have front matter).

You will need the actual url to move to the correct page - are you not able to do that for some reason?

at one point with posts there was a way to link to a particular post using the filename (?) so that the link worked no matter what the permalink was but that was only for posts and I am not sure that works still.

Jekyll has tags you can use to link directly to other source files. There is post_url when linking to posts. And link when linking to other documents.