There is absolutely nothing wrong with this...if you like the bag and your love croc, why not? If you are hung up on the "name brand" and everything about Hermes, then you wouldn't even welcome the idea. There are plenty of bags made in Italy that are amazing...the leather work and croc...it would blow your mind. These people are serious crafts people in Italy...Florence pumps out beautiful things. It is all about what you want.
I doubt this is illegal...would make for interesting research and new thread. I believe if Hermes has the actual Birkin design for themselves you would not see it (the design of the bag) at numerous high end boutiques that sell these fine leather and croc bags. I especially see them at highend Italian label boutiques near me. The bags are dreamy.