Nope, can't be done. I, too, would find it super useful. But it's Samsung's Galaxy Watch version of the Bixby button on their phones, unfortunately. Could be put to far better use if they'd let us.I would like to know this too. Did you ever find a solution to this? I would like to configure the long press of the top button to something else or at least disable the long press functionality.
Does anyone else know if it's possible to reconfigure the top button to something other than Samsung Pay?