How can I recreate this cloth effect in Celeste?

There are torn banners hanging from the roof in this Celeste level that are fluttering in the wind: https://youtu.be/cX9NJPwseIQ?t=202

This is a single sprite that's being animated. Is this done using a shader? A sprite skin perhaps? I've got a grass shader that's somewhat similar, but it doesn't have that clean cut pixel appearance.