The phrase is Brazilian Portuguese slang, with vixe used as an exclamation of surprise and que onda é essa roughly asking what is going on. As a short audio clip, it circulates mainly as a reaction sound for memes and short videos, where its informal, conversational delivery makes it easy to drop over everyday absurdity without needing subtitles for Portuguese-speaking viewers. Its staying power comes from that flexibility: the same few seconds can sound amused, doubtful or genuinely confused, depending on the scene it follows.