However, unless OEM data indicates explicitly that Vmca was done wings level, you probably would be better off presuming that the figure is for 5 deg into the operative engine - too much of a penalty otherwise as a general rule.
Don't know about A319 or 321 but following is mentioned in the abnormal procedures (Engine Failure on Takeoff) for A310:
Maintain speed at V2. Use sufficient rudder to hold a constant heading whilst maintaining the control wheel at about neutral. If a change of heading is required, aileron application should be limited to avoid an increase in drag due to roll spoiler deployment.
I am sorry if this post is irrelevant at this point of discussion.