You’re trying to setup Brave on new device and get this error while import sync code:
This code was generated by a deprecated version of Brave, please upgrade your other device first
You realize the older version of Brave generating a 24-word-string but the current one need a 25-word-string.
Now, the current 25th word is found at https://alexeybarabash.github.io/25th-brave-sync-word/, put this word at the end of your sync code then do the rest.
Warning: Brave does not officially support using the Sync code as a backup and you should not rely on this continuing to work in to the future.