Linking Error: UELinkerFixups.cpp.obj : error LNK2019: unresolved external symbol "void __cdecl EmptyLinkFunctionForStaticInitializationIwBpLib(void)

[Squareys]

You probably need to add IMPLEMENT_GAME_MODULE(FDefaultModuleImpl, BP);in your BP.cpp file or change whatever is there accordingly.

See
https://answers.unrealengine.com/questions/108534/lnk2019-errors-when-building-standalone-with-plugi.html
and
https://docs.unrealengine.com/latest/INT/Programming/Modules/Gameplay/index.html#multiplegameplaymodules