On the W-2 entry screen, you can select to "add another row" for local wages and taxes. If you have more than one W-2 from the same employer and all the information is the same except for the city wages and taxes, then just enter ONE W-2 for that employer and add a local wage line for each city tax wage/tax you had on the W-2's. See sample screenshot for adding another local wage line on the W-2.
