Pantheon's passiv and Yasuo's steel tempest

Hi, Here is the bug :

Pantheon's shield block Yasuo's Q ONLY when he's the first target. Else it doesn't block it. Pantheon's shield block Yasuo's third Q's damages when he's the first target, but he never block the bump.

I think it is due to Yasuo's Q applying On-Hit only to first target, but it is really inconsistent (the shield isn't really a On-Hit effect of the AA) and completely destroy the matchup. About the bump, which doesn't block the bump, i don't know.

Please, please correct this.