I’d like to suggest Xecrets File Command Line. It’s a GPL open source file encryption toolbox for Linux, macOS and Windows. It’s very flexible and is suitable for human use from the command line, as well as scripts and with the companion nuget Xecrets.File.Sdk it can be used as an encryption engine for .NET software.
For casual use there’s a (proprietary) desktop app frontend as well, providing easy and convenient working with encrypted files, also across Linux, macOS and Windows.
It’s 100% compatible with all versions of AxCrypt.
It works very nicely as an independent encryption tool for cloud storage synchronized from the local system to the cloud. It supports password-based as well as public key-based encryption.
See GitHub - xecrets/xecrets-file-cli: Xecrets File Cli - A feature-rich cross platform AxCrypt-compatible file encryption command line toolbox using a fork of original AxCrypt for cryptography. https://www.axantum.com/xecrets-file-ez is an easy to use graphical frontend for Windows, Linux and macOS using it, and https://www.nuget.org/packages/Xecrets.File.Sdk/ is a .NET SDK.. and https://www.axantum.com/ .
[Disclosure: I am the author.]