These include "The Goose Girl" where a serving maid takes the princess's place, and makes her a goose girl, "The White and the Black Bride" where the stepmother pushes the bride into the river and puts her own daughter in her place, and "The Lord of Lorn and the False Steward", where the steward robs the young lord of Lorn and passes himself off as him, with the true lord serving a shepherd.
Hans Christian Andersen's literary tale "The Little Mermaid" makes a variation not usually found in more traditional fairytales.
The Temple Girl fits the above prototype, since she gets the credit (which actually belongs to the Mermaid) for saving the Prince's life and wins his love.
An example includes the 1980 South African blockbuster film The Gods Must Be Crazy where the protagonist Andrew Steyn saves a group of schoolchildren from some rebels.
Steyn's rival Jack Hind acts as if he did the deed in front of both men's love interest Kate Thompson.