I have a 31.3" inseam and ride a 54cm Trek. I don't think I'd fit on a 56cm frame. 56cm would seem to be a bit tall for you from a standover perspective, although you might need the top tube length.
Have you ridden the 56cm?
__________________
“Courage is going from failure to failure without losing enthusiasm." (Churchill)
"I am a courageous cyclist." (SpongeDad)