It looks like Astartes 2 will be hosted on Warhammer Plus, the streaming subscription service that hosts animation, tutorials, and other media for 40K and the fantasy setting Age of Sigmar.

You may like Warhammer 40,000 animation 'Astartes II' looks stunningly ... As Space.com's resident Warhammer 40K nerd, I adored Space Marine 2 when I reviewed it last year calling it a "must ...

Space Marine 2 does not reveal the nature of Titus’ secret new mission (the Warhammer 40,000 animation in Amazon’s Secret Level anthology, which acts as a Space Marine 2 sequel of sorts ...