Both are free to download and contain the same features. They differ in how you buy Pro.
The simple route
Version 2.3.10 · 13 MB
The direct build is signed with a Developer ID, notarised by Apple and updates itself. Pro does not carry over between the two: a licence key works only in the direct build, an App Store purchase only in the App Store version.
NetMute is featured on these platforms and directories.