As TG says, you need a Honda dealer, Honda independent or someone with Honda HDS diagnostic tool to get any information out of the ABS ECU.
Without actually seeing the diagnostic, you're only guessing what the cost will be. A mechanical issue, replacement sensor, or wiring fault will be at the cheaper end, while a new ABS modulator fitted at Honda runs well into four figures.
You need the diagnostic to see what's going on, or at least narrow it down to one corner. It may even be a mechanical issue causing the ABS to play up, such as a wheel bearing.
The hub is the rotating part that the roadwheel bolts onto, nothing more fancy than that.