The gouramis may fight. It is best to give them a lot of heavy plant cover, to break up sight lines, so they are not having to see each other all the time. Floating plants too, for shade, and very little water current. They are fragile fish that often do not live for long, which is quite sad, since they are so pretty.
The barbs may harass a gourami anyway, especially if it is weak. They prefer tankmates that are less boisterous, but the barbs do tend to chase each other more if there are enough of them, so hopefully it will be ok.