Actually, Midoriya did not give his quirk to Bakugou in the movie "Heroes Rising". Instead, he used a new move called "One For All: Full Cowling 100%" to transfer the power of One For All to Bakugou for a limited time.
In the movie, Midoriya and Bakugou were fighting against a powerful villain named Nine, who had the ability to steal and combine multiple quirks. Midoriya knew that he and Bakugou were not strong enough to defeat Nine on their own, so he decided to entrust Bakugou with the full power of One For All.
With the help of One For All, Bakugou was able to defeat Nine, but the power was only temporary, and the quirk returned to Midoriya once the battle was over. The reason why it returned to Midoriya is because One For All is a quirk that can only be passed down through direct physical contact and cannot be permanently transferred to someone else.
