use ThreeJS’s ConvexGeometry and ClippingPlanes. But when I exported the scene using GLTFExporter, I found that the generated GLTF file cannot save the clipping effect.

[donmccurdy]

See:

GLTFExporter exported model without saving clipping effect

Yes, not all feature of three.js can be saved to standard (engine-agnostic) formats. Clipping planes are one such feature. If you only need to reload this export in three.js, you could use object.toJSON() instead, and load the result with THREE.ObjectLoader.