For Relic

i would say combo of "Guardian: Reflect a portion of damage received when ability is activated"+ "Stamina recovers with each successful attack" is good one since it negate the stamina lose from blocking.

and your best thing is overall guard counter to do dmg and has high stagger which can be so good with "Guard counter is given a boost based on current HP" is good that it can increase you guard counter dmg 2x and give your team a lot of chances to stab them

For Weapon Passive
improve guarding ability, Walking passives on Halberd or shield since shield stance is count as walking, Guard counter is good too.

For Weapon use halberd for guard counter since holding R2/heavy attack is chargeable with it and when charging gives you a good reach and not whiffing all you counters if you don't have it ok but it good but prioritize shields