
Sinclair is not a mannequin.
Sinclair is a character that invites many fan redesigns because their current design is one of the more unfinished ones, especially compared to the last twelve. Some of these can be very drastic which gets them criticized. I’ve seen people shut down the whole design since it was straying too far from the original purpose by not keeping them a mannequin. This is a common thing I see regarding the character even though Sinclair is never said to be one.
Sinclair is not meant to be a mannequin. That’s just something people latched onto because of the way they look. And the only reason they look like this is because they use the generic test model. The same kind of model you see running around when you’re in the testing grounds. Sinclair is not supposed to actually look like this which is made even more clear once you factor in all the stuff about theme in-game.
Nothing in Sinclair’s lore states that they’re stuck in a mannequin. It says that they’re stuck in the same body, but never says what that body is. And when it comes to other characters, none of them ever talk about Sinclair looking one. Currently the only line we have on Sinclair’s appearance is Silver calling them an asshole in a top hat. If their body was a mannequin, you’d think one character would actually mention it.
Deadlock is far from finished and everything is subject to change. It’s possible that Sinclair’s final design could turn into them possessing a mannequin, but for now their current design is very much a work of progress that’s not indicative to what they will look like outside of being a magician.