At Swan/Dolphin, Kimonos is open until 11:30pm - so a little later than all the others around there that close by 11pm.
As far as I know, the latest food service on Disney World property is Three Bridges over at Coronado, which is open until midnight. If you've got a car, it's a short just-under two mile drive from the Epcot resort area. Great food there too - I'd prefer eating a late meal (and cocktails) there over Kimonos if I had the choice...but that would mean having a car or getting a lyft/uber if you don't have one.