This requires AutoHotkey.dll from AutoHotkey_H v1 in an appropriate location for DllCall to find it, such as the current directory or the directory containing AutoHotkey.exe.
This was meant to be a quick proof of concept, but it turns out to be trickier than I thought. To retrieve functions, classes and other objects from AutoHotkey.dll and use them safely, it is necessary to manually marshal the object's IDispatch pointer. Otherwise, the script will most likely deadlock when the object is used, because it will be called on the wrong thread. Marshalling gives the v2 script a COM proxy object which takes care of forwarding calls and return values between the v2 thread and the v1 thread.
I realized after posting it that thqby's script probably already does something similar, but I haven't tested it.
CodeQuickTester
@geekdude