Heck, I wasn't offended.
The copy could never really be exact, unless all your mechanics and effects were the same as the other game's mechanics and effects. Which isn't likely unless both are faithful replicas of a the same pen-and-paper RPG. Which doesn't describe anything I'd be likely to implement, so no risk there. :-)
So while I could read the monster definitions file and see that something has, say 4d6 damage and a base-to-hit (based on monster hit dice) of, say, 16, I'd be using that to base a different set of values on - what does that stuff mean, in a game where characters start with more hit points than the d20 system it's based on, but high-level characters have less hits than high-level d20 characters? Where the base-to-hit from d20 has no very close analogue because we're using a normal rather than linear distribution, and where damage is divided between short-term (stun and endurance which require rest) and long-term (cuts and bruising which require healing)? And where healing rates and availability of healing effects is different from the source game? And what does a special attack form mean if the means of resisting or recovering from that effect is different or harder in one game than in the other?
Then what does the fact that in the source game a monster appears on levels 20 to 40 mean if my game only has half as many levels, but they're twice as big, the original has unlimited level regeneration and my game has persistent levels, and player progress through levels is likely to take less time near the beginning of the game but more time toward the end?
I mean, yes, you can write a straightforward translation function by picking some set of assumptions, just as you have to make assumptions when you're translating from English to Russian to Chinese - but no, it's never going to be exact, any more than a translation from English to Russian to Chinese will be exact. The critter would be recognizable, and similar in scope and threat - but it would never mean exactly the same thing strategically as the original meant in the original context.