Having wildcards in the path for AdditionalPluginDirectories causes apps on Android to crash on launch. When testing this on iOS, the app did not crash but froze at the splash screen instead. Android logs are provided but I'm currently having difficulties getting logs off the iOS device for this issue.
Note: It's possible that this crash is expected, based off the assert message. If that is the case, another bug will likely need to go in as the wildcards that are causing this are automatically added to the path when a plugin is enabled/disabled in the editor.
This also occurred in 4.15.3-3450819+++UE4+Release-4.15
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-46455 in the post.