[2021] necroids species

What platform are you on? It has not been released for consoles yet.  

June 17 was the released date for Federations:

Federations Now Available for Stellaris: Console Edition!

Expansion Pass Four, Federations, and the free 2.8 Update are Now Available for Stellaris: Console Edition! In Federations, the supreme art of war is to subdue the enemy without fighting. Pass powerful Resolutions, form new Federation types... forum.paradoxplaza.com
I'm not aware of any announced date for Necroids but it would never be only a month between releases. Where did you see July 17?