Hi, thanks for the feedback. This should already be possible for you to implement on your site.
The issue is that the Webflow redirect is not aware of the existence of paths that include Weglot subdirectories. So, in your example, if “fr” is the Weglot language, you can’t redirect “/fr/my-old-page.html” to “/fr/my-new-page.html”, because Webflow does not know that the “/fr/…” pages exist. They are added on top by the Weglot proxy.
However, you should be able to use the original-language path to do the redirect in Webflow. For example, if you simply redirect from “/my-old-page.html” (without the /fr/) to “/my-new-page.html”, the redirect should work, and Webflow will transmit this to Weglot so that it holds also also across the /fr/ language.
Please let us know if this is working, and if not, please don’t hesitate to also contact the Weglot support channel directly so that we can look at your use case more concretely.