Depends on what your metrics for 'better' are. What I deem as important may be something you don't care for.
But being as objective as I can, of the three, I think the iPhone XS Max would be the best for the general consumer, then the Note 9, then the Pixel 3 XL. If you have specific things you really like, then go see how those three phones address them and decide from there, but I think the iPhone XS Max is the best overall device. Has the cleanest and easiest to use user interface, great features, iMessage is excellent, great cameras etc.
Note 9 looks like the best android consumer product as it offers a tonne of functionality, great battery, speedy performance and all around great cameras.
Pixel I'd say is more of an enthusiast device for those who really know what they want. It doesn't offer as much as competitors and isn't as competitively priced, but it also offers a unique set of features, great cameras and great user interface.