Thanks to the 64-bit debugger in Xojo 2017, we can now easily try 64-bit applications and that's a must as Apple's latest frameworks don't support 32-bit anymore.
So yesterday and today I worked on a test project including a Xojo plugin for CoreML framework. Here is my test project running:
While macOS 10.13 is not ready for a few months, we can already download the beta versions of macOS and Xcode and play with it. You can use a model quite easy as you see in the Core ML presentation from WWDC 2017. With just a few lines of code we load a model, setup source image and run it though the neural network to classify the picture. You can get sample models from Apple's Machine Learning website.
The plugin will be available later this year with the macOS release.