I don't know what engines the Braz has. With the PW12x on the DHC8 there is nothing (apart from the triggers, which are not locked out in flight) to prevent you from retarding the power levers below the flight idle detent.
I would suggest that if a power lever were to inadvertently be moved aft of the flight idle detent in flight, the result would be a propeller overspeed, and most likely blade separation long before reverse would be possible.
Neither is desirable, however.