Thanks for the replyDefinitely legitimate. I've seen both home and away Adelaide Crows guernseys from 1996 and 1997 with Puma retail tags.
I can't with all confidence give you the full backstory on it, but Puma did have a retail license for the AFL at the time and I believe had the contract to manufacture the Crows retail guernseys. My feeling is that it's to do with Adidas, at the time, not having the capability to make a sublimated AFL guernsey which was required for this design (debuted in the 1996 Lightning Premiership IIRC), or the club simply preferring the Puma "Coolmax" fabric compared to whatever Adidas had developed.
Weird things going on in those days, apparently.