Command Line (or minimalist GUI) usenet poster for binaries developped in C++/QT designed to be as fast as possible and offer all the main features to post data easily and safely. Releases for Linux, Windows and MacOS are available.
A bit of a different tack: consider whether you even need to use a password. I made a comment here to the tune of thinking it makes little sense in most cases. Do passwords actually provide any more protection than obfuscation? Before mindlessly answering 'yes', consider the fact that passwords aren't actually used for secure encryption purposes in Usenet (since the password needs to be shared around), but rather a fancy form of obfuscation. Unfortunately, I don't really have any hard evidence one way or the other, so I don't like making this point (though I'd argue that proponents don't have any evidence either), but I think it's worth the thought.
Flexible usenet binary posting tool
It was mentioned that encryption/password protection may be reason why you'd stick with RAR.
Appwrite - The Open Source Firebase alternative introduces iOS support . Appwrite is an open source backend server that helps you build native iOS applications much faster with realtime APIs for authentication, databases, files storage, cloud functions and much more!
Usenet Posting - Obfuscation, PAR files, RAR uploads and other things
4 projects | reddit.com/r/usenet | 11 May 2022
Upload all files inside folder
2 projects | reddit.com/r/usenet | 3 Jul 2021
Uploading to usenet with no SSL. Safe?
2 projects | reddit.com/r/usenet | 29 Apr 2021
Large binary post PAR2 help please
1 project | reddit.com/r/usenet | 5 Apr 2022
Is it possible to stream the videos instead of downloading it?
2 projects | reddit.com/r/usenet | 17 Nov 2021