Butcher is reduced to €5.49 on Switch eShop.
Hollow is €3.99
The VideoKid is €4.39
Edit: Nintendo gives you a points thing when you purchase from the eShop, so it seems these games can end up being even cheaper than the price above (they were for me just now anyway - Butcher worked out at €5.27 from points I already had, and hollow ended up costing €3.72 after the points I got from purchasing butcher).
I don’t think I didn’t anything special to add these points to my account - you could just add them with the coin button when purchasing.