Outlast 2 How To Get Past Marta (Pickaxe Witch Lady)
One of the main antagonists you encounter is named Marta. She is a long-haired witch-like woman with a giant pickaxe. You may remember her from the very end of the Outlast 2 demo, where she does something unspeakable to your genitalia.
When you encounter Marta in the full game, though, you'll likely die several times before figuring out how to get around her. Unlike other enemies, Marta isn't someone you can easily sneak around, and, if you meet eyes with her, it's probably already too late.
You'll encounter Marta emerging from a house after you've just slid down a hill. Before you trigger her encounter, be sure you grab the battery in the little shack to your left.
After that, you'll need to juke Marta. That is, grab her attention, and make sure she's running toward you, and then run a circle around the aforementioned shack, before heading directly for the area from which Marta entered. Pass the house, and run to a barn where you'll notice a small hole under the fence. While running, hit the prone button (C on PC), to dive under that hole and crawl into the barn.
After this you will be safe. From then on, always watch for paths around which you can juke Marta. Hiding and running away don't do the trick.