Pioneers is a building strategy game in the tradition of the Settlers series, of which I was a great fan until Ubi ruined it.
Foundry is a mix of factory/automation simulation comparable to Factorio or Satisfactory - and minecraft. With a big priority for factories, and decent system requirements.
Both make a great impression for now, although there are no story elements yet, and no enemies.
So it's just building up your economy. Which is okay for a start. I put both on my wishlist, and I will most probably buy into pioneers on start of EA indecember.
I have small doubts on Foundry whether it will be fun in the long term. Because by now it's "minecraft part" consists only of the materials dirt and stone. And since the factorIes themselfes look rather ugly (compared to satisfactory) I would wish for many stuff to build pretty buildings around them.