No, WiiM is the AirPlay 2 receiver not a transmitter. Only the following Apple devices or software can work as the AirPlay 2 transmitter that you can stream AirPlay 2 audio from:
- iPhone, iPad, or iPod touch with iOS 11.4 or later
- Apple TV 4K or Apple TV HD with tvOS 11.4 or later1
- HomePod with iOS 11.4 or later
- Mac with either iTunes 12.8 or later or macOS Catalina or later
- PC with iTunes 12.8 or later
However, if you have multiple WiiM Mini, you can play the aux-in audio on another WiiM connected device (or multiple devices). Please find the guideline from https://wiim.freshdesk.com/support/solutions/articles/72000524952