I've been reading a text and all three of these come up 影 vs 形 vs 形状. I know they mean shape/figure, but is there a more nuanced difference between them? I can see the logic of where they are in the text but I can't figure out the difference.
If you are familiar with the general difference between on-readings (音読み) and kun-readings (訓読み), you already know the basic difference between 形【かたち】 (kun) and 形状【けいじょう】 (on).
The primary meaning of 影【かげ】 is shadow or silhouette, not shape, in modern Japanese. A few certain words, such as 月影【つきかげ】, contain 影 to mean shape, but I think such usage is archaic or poetic.