Not a problem when your talking about, ....Washing Machines, Tumble Dryers, Cookers, Dish Washers, and the bigger Fridge Freezers etc!! These will almost always be 220/240 volt. As for the 60Hz, ...it's not going to cause much of a problem, in fact you'll hardly notice any difference on these types of appliances.
Had exactly this situation while working in the Middle East. The company bought all American White goods for our apartments. All were 220 volt/60 Hz ...When the local supply was European based, ..ie 230/240 volts/50Hz. One of the few things that was obvious, was that you couldn't take any notice of the cooker clock/timer!! All were still working perfectly well when i left 2.5 years later....