I've just tried the link on the Magisk module description and it is working fine.
This is the description of the module:
"Systemless Xposed Framework
This module is only for Android 5.0 to Android 8.1!
Please install my modified XposedInstaller(3.1.5) to properly detect Systemless Xposed.
The APK is signed by my personal key, you might need to uninstall other versions before installing mine......"
The "XposedInstaller(3.1.5)" links to: (open with browser or download manager, it will trigger the apk download)
I myself using this apk with this module and all working fine with Magisk v19.3.
Thank you again!!