Being division rivals, there is plenty of history between the two. Take a look at some stats from their matchups over the past 5 years (pulled from StatMilk.com):
Applying IDP Projections
Raw stat projections are pulled from FantasySharks.com. Cincinnati should have the edge against the Pittsburgh running game overall, but may not run as effectively against the Steelers line. The Bengals should have above average coverage against the Pittsburgh passing game, except going deep, which may not even play a factor.
As for the specific player matchups:
The Bengals RB's appear to be more likely to hit their projections (depending on who sees more carries), but unless the Steelers are able to hit deep, expect the lower end of their projections. Even though AJ Green has a more difficult matchup compared to the average, he is going to be more likely to hit his top projection than Mohamed Sanu.
Here are the specific defensive projections for match-up references: