Sanic is Flask-like, whereas Quart is the Flask-API (some Flask extensions work with Quart https://pgjones.gitlab.io/quart/flask_extensions.html#suppor...).

The key part I wanted to highlight here though is that Quart serves HTTP/2, which I think sets it apart from most of the other Python frameworks. (I know Twisted also does this https://medium.com/python-pandemonium/how-to-serve-http-2-us...)