The modern figures don't represent any one game or period, other than that the characters' styles are all "Post Sonic Adventure", so any game the came out after that, is eligable for one of these 20th Anniversary figures. Here is the MIB shots for Shadow & a Mono Beetle.
Shadow's date of 2000 is wrong, as he didn't appear until Sonic Adventure 2 which was in 2001. Will they do a second run of these with fixed dates? It looks kind of funny/fishy this way because the very FOCUS of the line is about DATES and then they got them wrong on the box. 

MonoBeetle (came with Shadow)- This is a GUN made item (not Eggman) so it's military-plain. It's a solid slug of plastic with 0 moving parts. It's well sculpted, with bolts, vents & hatches and the cut for the turbine fan thing is nice. It's a great representation of this simple enemy. (but it seems sort of an odd choice to do a figure of, is anyone a 'fan' of this thing?)

Photo by TurboTheHedgehogSomething's amiss with this Shadow figure! He's on the wrong card. The background, you can easily tell is actually Sonic Colors--a game he wasn't even in. It's not a common mistake, but be sure to look over the figure & card before buying so you can avoid it. It doesn't make the figure more valuble, it's just a sort of neutral mistake--ok to collect if you find it interesting.