Ah, sorry, you had mentioned buttons so I just assumed it was a specific element you wanted to watch.
You want Borders.
You can place as many other elements as you like on them, and adjust their transparency to make the border itself hidden(leave it visible, just set the alpha to 0)
It has an OnMouseMove event that only takes place when the mouse moves over the border itself.
By placing a larger border (Exit) around the one containing the elements you want ‘blocked’ (Enter) - you can turn the boolean showing that the mouse is over that area on and off.
In this case I used Green for the “Enter” border and Red for the “Exit”
(the little red button was to ensure it worked, which it did)
.
Then just bind the OnMouseMove for each to set the boolean.
