Dynamically create DLL export functions without having the preprocessor involved in MSVC 2015?

Question

Is it possible to dynamically create __declspec(dllexport)'ed functions without having the preprocessor involved in MSVC 2015?

I'm creating a DLL plugin-creation toolkit for some kind of measurement software and want to make the later client-programmer being able to add some kind of "extra-features" to the plugin in the DllMain, e.g.:

// Create a new instance of the custom driver
MyPluginDriver *myPluginDriver = new MyPluginDriver();

// Assign it to the core DLL
pluginCore.addDriver(myPluginDriver);

For each of this addDrivercalls, the DLL later has to provide a callback function, whose name can be freely chosen. The main app expects the names of those functions getting passed by request in another callback.

So, what would be the 'best practice' for generating those extern "C" functions dynamically whithout #define's and stuff?

Maybe some kind of Lambda way?

EDIT: I think I've forgot to mention that it's a commercially available measurement software for which I'm writing that PDK. It's a fixed interface (and a fairly complex one, too) of hard-coded and expected function names by the app for the general callbacks. There's only that particular callback expecting some function names to call for measurement cycles which is relevant here.