Can One reduce stage fuse into another reduce stage?

I’m not sure what you mean here, but if I take it literally, that wouldn’t be feasible.

But there is an example of scheduling fused conv2d → conv2d: tvm/tests/python/contrib/test_hexagon/test_conv2d_conv2d.py at 6aa5ba281ba669d01038ca67b2f6d55ba2299249 · apache/tvm · GitHub