Redirect by language

I’m using Gatsby and have created a _redirects file with rules and it’s working fine. We have now added multi-language content and I want to redirect like:

If user is language=en and is on the german page (de), I want to redirect him to the english version instead. So:

would redirect to

I’m trying to do it like this but I’m seeing no effect of it.
/en/* /de/:splat 301 Language=de
/de/* /en/:splat 301 Language=en

This one for the root domain works fine though:
/ /de/ 301 Language=de
/ /en/ 301 Language=en

What might be the problem?

@chrille112 If you’ve produced a single page application (SPA) with Gatsby, then subsequent page changes probably aren’t even reaching out to Netlify and encountering the redirects, it’s probably all internal Gatsby routing.

If it’s just the initial redirect you’re trying to perform when the user first hits the URL, then I’d imagine that should work provided that it ends up loading the SPA.