>>95922941
>Blood claws have the pre mkX legs
They have mk10 legs. You can very clearly the thigh armor with the details that mk10 has. Same with the ankles which have the mk10's ankle ball and the distinctive foot shape.
And you can see the chestplates these guy's have, it's the same mk10 chest plate that has the extra plate on top and many have gorgets too.
Even the powerpacks are mk10, but they just took the small plates off the ball shaped vents.

They are just mk10 without some details, but it is still obviously mk10.

https://www.warhammer-community.com/en-gb/articles/hx9biq5l/these-epic-new-space-wolves-will-write-sagas-worthy-of-the-allfather/
Full article where you can look at the marines.