FileLoadException from netstandard.dll in installed version but not in debug

We ported our base libraries to netstandard2.0 and consume them in an wpf net461 application. While debugging in visual studio everthing works fine.

But when using the release version installed via setup we get an fileloadexception.

FileLoadException: 'Could not load file or assembly 'netstandard, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131044)'

I verified that the setup installed everthing needed and that the binding redirects are corret. But still i get the exception.