My game uses tab as a hotkey for something else. I would like to completely disable the Noesis functionality of having it switch focused control. It's very disorienting to have it keep moving the focus all around the UI when I am trying to target something.

You can hook to PreviewKeyDown event and set e.handled to true for the Tab key, that way keyboard navigation will ignore it and focus won't be affected.
Could you try that?

That worked - Thanks!

Great, marking this as solved.