Download of YubiKey Manager 1.2.5 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The software lies within System Tools, more precisely Device Assistants. We recommend checking the downloaded files with any free antivirus. This free Mac application was originally created by dev.yubico.
From the developer:
Python library and command line tool for configuring a YubiKey. The package is brew compatible which means it can be installed automatically with the packet manager. Through the terminal you can manage connection modes, OATH credentials, and OpenPGP keys.
You may want to check out more software for Mac, such as Soccer Manager 2015, MeD's Movie Manager or Soccer Manager 2017, which might be related to YubiKey Manager.
Device Assistants
Device Assistants