In terms of PvP, can all assassin blade skills (blade shield, blade fury, blade sentinel) be blocked? And do those skills always hit or rely on attack rating?

yes you can block them, yes they check vs def

This post was edited by fatal123 on Sep 2 2023 11:38am

Vouch.

Additionally attackrating bonuses from claw mastery is not applied.

I did some research:
https://forums.d2jsp.org/topic.php?t=94840990&f=87

Thank you @fatal123 and @gel87 for the feedback. Good stuff to know these as there are a couple of bladesins here in Asia server whom i cannot defeat as a pure vita BvC.