Akihabara has a one of the most famous restaurant in the whole world. It is a traditional Japanese sushi bar but it is not usual. Because all sushi chefs are women . Please check it out them website. http://www.nadeshico-sushi.com/index_e.html
I think that you guys should try it! Absolutely
There are not so special food in Akihabara.
Depends on you if you have any specific Japanese local ,traditional or any other special foods in Japan.