Microsoft is planning on deprecating support for the Translation feature in OneNote for Windows 10 during November 2023. After this date, OneNote for Windows 10 will continue to be supported, and the translation feature will remain visible but, will show an error when used.

The translation feature in OneNote for Windows 10 is itself a web-type feature.
When you use this feature for the first time, you will be prompted to send your page to the website for translation.
After November, the site disconnects from this connection.

https://support.microsoft.com/en-us/office/deprecating-translation-in-onenote-for-windows-10-7a09cfa4-32de-486a-9c7f-965eeeba3439