Unity is unable to find native libraries.

I'm using the latest Unity Editor on Linux and I added several native libraries of a program I need.

The problem is that nor the Editor nor the Builds are able to find them.

I placed the libraries in the Plugins folder in their corresponding places: x86 and x86_64 for Windows, Mac and Linux; Android/armeabi and Android/x86 for Android.

For the desktop libraries I additionally configured each one for their specific platform: x86/*.so for Linux 32 bits; and so on.

I was able to find the origin of problem in Linux: When searching for the library, it searches in the wrong folders. It searches in the app_Data/Mono/x86_64/ folder instead of the app_Data/Plugins/x86_64/.

On Android it simply says Unable to find mylibrary.dll.

Is this just a Linux Editor issue or an overall issue?