After 15 years with the license, are there really any DC characters Mattel has yet to do? It turns out there are!
In the '90s, Wonder Woman got a new sidekick. Donna Troy was still around, but her history was so convoluted
at that point that nobody really wanted to do anything extensive with the character (or perhaps that anything they might have wanted to do would have already been done and undone, perhaps more than once). Thus, John Byrne introduced Cassie Sandsmark, the daughter of an archaeologist and museum curator, who was fascinated by Wonder Woman. After proving herself to be a hero, Zeus granted her real powers, and she joined other teen heroes as a part of Young Justice.
(Cassie also appeared in the New 52, but there her origin and powers were entirely different: her father was one of Zeus' many children, making Wonder Woman her aunt; her mom was still an archaeologist, but Cassie chose to act out by stealing from museums and art collectors; she and her boyfriend found a semi-sentient suit of alien armor, and she put on the bracelets that allowed it to bond with her; though it can turn invisible, Cassie is always wearing the armor, and that's what gives her her abilities.)
Given that this is a Mattel product, there is a surprising amount of new molds on the figure. Her bracelets are raised elements, but those might be reused from Donna Troy; ditto the high-heeled boots, which are like Black Canary's. But her crop top has the raised WW logo, and she's wearing jeans, so the lower torso gets a molded belt, some seams, and a fly. She's even got a belly button! For a company whose ability to repaint a few basic molds outstrips even Hasbro's, this is impressive.
Of course, it's still Mattel, so there needs to be something glaringly wrong, doesn't there? Well don't be scared, they still managed to completely drop the ball. Although Cassie Sandsmark has aged and grown since she was introduced in the comics, she's still a teenager with a teenager's body. Mattel, not having a teenage sculpt they can repaint, has given her normal adult legs, meaning she's just as tall as the women - nearly 6½". There have been several stories where the Teen Titans meet their future selves, but she didn't wear this costume in any of them (rather, a version of Wonder Woman's outfit), so you can't even claim that's what Mattel was going for. Because they're unwilling to invest as many resources in their toyline as Hasbro is, they delivered a sub-par product.
The head's nice, though. It's got the same look the Four Horsemen gave all the DCU Classics, but without the general flatness a lot of those early figures had. There's something about the paint on the eyes that has a cartoonish feel - maybe the idea was for this figure to fit in with the Young Justice figures? That seems unlikely.
The articulation is mostly standard: a balljointed head, swivel/hinge shoulders, swivel/hinge elbows, swivel wrists, a chest joint that seems like it's meant to be a balljoint but is barely only a swivel, swivel/hinge hips, swivel thighs, hinged knees, and hinged ankles with absolutely no kind of rocker motion. The best thing we can say is that the hair is sculpted to hang away from the shoulders slightly, and that the head can actually look up and down a little bit. That's more than most Mattel DC figures can claim, so good for her being able to do one basic thing right.
Wonder Girl has no accessories - he's got her magic lasso (technically the same one Dark Knight Wonder Woman had), but it's permanently attached to her hip. She does get the legs and head of this two-figure series' Build-A-Figure, Dr. Psycho.
DC Direct released a Wonder Girl æons ago, and while the articulation on this Mattel action figure released in 2018 is better than a DC Direct figure released in 2004 (shock!) and that old figure was molded permanently holding her lasso in her fist, if you want Cassie in your collection, DCD's a better choice.