How does upper hand react on no guard?

Question

Does it always flinch, effectively stun-locking a no guard user or maybe even working with some sort entrainment/skill swap?

Answer 1

So No Guard doesn't really do anything. Upper Hand already has 100% accuracy and No Guard doesn't do anything unless accuracy is lowered. However, No Guard only gets rid of Accuracy checks, not move mechanics. IF the target doesn't use a priority move, upper hand will fail. IF the target does, Upper Hand will land and flinch the target. This is the move mechanic so no guard does nothing!

Source
https://www.pkmncast.com/classic/2011/6/10/aotw-no-guard.html
https://bulbapedia.bulbagarden.net/wiki/Upper_Hand_(move)

Comments

No guard does let moves hit Pokemon that are using fly, dig, dive, bounce, etc, but it still doesn't let upper hand ignore the priority move check.