Yes, this movie should have foreshadowing in it. I thought of some examples. - The climax officially reveals that Brick is jealous because of Blossom's crush on Jared. This could be foreshadowed earlier in the film when the Rowdyruff Boys meet Jared, because once Blossom mentions liking him, if one notices Brick's expression he appears to be envious. - Bliss's sacrifice will get foreshadowed. At the beginning when Bliss it talking with the PPGs they talk about ways they could lose her. One of them is sacrificing to let someone else get a hero moment. - The RRBs becoming good guys. When we first see them in the film Brick is telling the other two their plan, but Boomer isn't paying attention to him, and Butch just sighs presumably in annoyance. Then Brick tells Boomer to stay focused and tells Butch that it's a good plan they're doing.