Creation of (only) visual content for an online course

The project consist of creating visual content only (either using Power Point or another software) to add to audio files I will provide to create a series of lessons for a 2-hour course. Each lesson is around 5 minutes long. In other words, I will provide a series of audio files and the freelancer should add visuals synced with the narration of the audio file. Narration in the audio files are in Spanish.