No, just like in real life we don't know what the scouting department of another team thinks (otherwise we'd be quite good at mocking the draft!).
What we do have is the media's opinion of a player, which is the best we have. (I think that answers the first question, I wasn't too sure if that was what you were asking or not).
There are different strategies in the sense GMs/HCs prefer different player types (like a power back vs a scat back) and rate the players according to this.
A team which runs a 3-4 is going to value a OLB or a NT far more than one which runs a 4-3. I hope that answers your second question!
