Hi!
I made a PR with missing Polish translation: https://github.com/NodeBB/NodeBB/pull/14298
345
I know the bot referred me to https://explore.transifex.com/nodebb/nodebb/, but registration there currently requires a specific business email address, and Google or GitHub logins don't work, so I can't help you that way.

It would be great if you could implement translation. I can also help or delegate people in the future. I have a Polish-language forum.