Yes, I was absolutely bored when I decided to do this. But interestingly enough, I have some results.
https://i.imgur.com/Pgp12m7.png
First things first! Joker’s mug shot is what made me consider doing this in the first place, as the background is clearly marked to show increments in 5 centimeters. From this, we can tell his height is approximately 175 cm (about 5 ft. 9 in.). Notice where his elbow rests: nice and centered at the 115 cm mark. But because of the held sign, it’s crooked at an angle.
https://i.imgur.com/DPuNOHO.png
Marking the distance from the shoulder to his elbow (blue line) and setting his shoulder as the pivot point, we can see at what height his elbow would be when placed at a default resting position (red line). This would bring his elbow’s natural height to about 113 cm, shown by the yellow line.
https://i.imgur.com/jvAfL53.png
Next up: Lavenza appears! With her standing next to Joker, this is a great chance to compare their sizes. Using the distance between identical parts of the two guillotines as a point of reference, the thin red line shows how tall she is compared to Joker while taking the camera angle into consideration. In other words…
She’s right under his crooked elbow.
Now this is of course assuming the animated cutscene shows a 1:1 match with Joker’s in-game model, but if he were to “un-crook†his elbow, the distance doesn’t seem to be that far off from the estimated resting position, right? So with that in mind, Lavenza’s height should be around 113 centimeters, or about 3 feet and 8 inches. Almost the height of an average 6 year old girl.