Are you aware of the three.js sample for cloth sim (three.js examples)? It uses ammo, so won’t play nice with our physics directly, but might work for cloth-only apps. I don’t think Rapier (physics engine we’re using) has an integrated specific “Cloth” component, but the “Joints” demo here looks cloth-y: Rapier3D JS bindings demo
We also support a bunch of joints already - not sure if that would be enough for you to make something closelike. The samples repository contains a small scene for that