If crushing blow will work, and each echo can be 10 hits, thats potentially 10 crushing blows with 1 hit, which would be very nice. That could bring a T5 P8 herald down to 25% just from the 10 crushing blows (just 1hit). I put potentially and could in italics because that is assuming 100% hit and CB rate, which is now statistically impossible. But the crushing blow could be true if big.
Nope
Smite always hits, it still applies CB
ES not applying CB wasn't because it wasn't performing a hit check
it was because they disabled it, voluntarily, just like ctc% on hit/attack
People need to stop thinking that they will buff ES by re-enabling what is voluntarily disabled.
They want to nerf it, not buff it.