Apple Mach-O Linker (id) Error

This really starts to annoy me.

I googled and tried different "solutions" for this and either I find outdated stuff or it led me to more errors.

I'm using Unity 5.6.1f1 Xcode 8.3.3 Vuforia 6.2

The Error I get is:

Apple Mach-O Linker (id) Error

Undefined symbols for architecture arm64:   "_OBJC_CLASS_$_ALAssetsLibrary", referenced from:       objc-class-ref in ImgTOAlbum.o ld: symbol(s) not found for architecture arm64 clang: error: linker command failed with exit code 1 (use -v to see invocation)

Android works perfectly fine. I know iOS could be a bit more picky about certain things. I'm using the Region Capture Plugin ... but I found that other users managed to bring it on Apple as well.

So what can I do about it?

I tried to disable Bitcode, Dead Code Stripping is enabled... I'm slightly running out of possible issues. Any help is really appreciated. Thanks in advance