Your defrost strategy is relevant as well, as you don't want untempered air dumping in the space. Exhaust only defrost is my preference for small HRV.
Ventilation should be sized on people (cfm/person) and area (cfm/ft2). Also, you may be exhausting for industrial purposes? Washrooms?
I'd check the off HX temp on your HRV at design, drop it by 5 degrees then picture it dumping into the space. If that is acceptable, no reheat required.