@Mike42 if that’s the only way you did with passwords, you may be out of luck. Passwords are encrypted based on your OS keychain. If you just yanked the Brave folder and then changed up your OS in a way that would change the keychain, then it no longer would have the encryption key and there’s no way for you to get it. So while passwords are there, you would not have a way to see them.
Bookmarks should be there, but that’s only if you copied right. Everything would be stored in the User Data portion of \brave-browser folder. If you copy/paste that over, it should have the majority of your data, with the only possible issue being passwords because of the encryption.
The best method for backup would have been to done an Export Bookmarks and Export Passwords. Or to have set up a sync chain with another device (such as your phone) or to have quickly done a sync chain and done the change on OS and add back to sync within the same day (as sync phrase changes daily).