Instead of Barb, Crush is a power hungry villain and they plan to steal all the strings to turn the world into a union of Pop/Country/Techno/Funk. You can still do it in the second movie, only with crush as the power hungry villain

If your crush is a Pop Troll, they will create a union of Pop

If your crush is a Country Troll, they will create a union of Country

If your crush is a Techno Troll, they will create a union of Techno

If your crush is a Funk Troll, they will create a union of Funk

(Similar to when Barb first came to Techno Reef to steal their string)

Amy's original looks:

Amy's Techno/Country Zombie form (when Trollex played his DJ booth with all the strings and was about to use it on Poppy, but Amy rushed forward and pushed Poppy away, taking the hit):