From the current event we have the new M2 Mortar only available in the Normandy campaign. In all other American campaigns they use the British two-inch mortar. They should add the M2 to all American campaigns/ maps. Plus they can add the heavier M1 and M2 4.2 inch mortars eventually to the faction
I will say theoretically we should be able to use the M2 Mortars in other campaigns after the new major overhaul but we’ll have to see