It's only rock and roll
There are six Hard Rock Cafe's in Japan. The one in Yokohama is conveniently located in the touristy area of Minatomirai -- the Central District of the modern city. The Hard Rock is located at the base of one of the Queen's Tower's shopping malls and almost across the street from the famous Yokohama Museum of Art.
There are 100% English menus and the entire staff is fluent in English. The menu is what you expect from a Hard Rock Cafe. Lot's of stuff that likely isn't healthy, but delicious! The Chicken Tenders were especially tasty.
Below the Hard Rock is Minato Mirai's train station. One floor up is a Krispy Kreme Donut store, just in case you have room for a little more food.