I don't know if this was known already but I just found it is possible to go onto the through walls on the game. Not sure about how easy this would be to reproduce and whether it would be of use in runs but I think it had something to do with sliding into a wall a certain way after running out of stamina, would do you all think? https://gyazo.com/4c458951dc79a4b2ff46986470e0aee3 heres a photo for some evidence

You can clip through walls with a Horse but only specific walls with land behind them. Also there is no way to clip back in bounds after you clip in the walls.

Yes that's true, you can't clip back in bounds but on some you can. On the way to hateno village, you pass through this narrow path in between rocks (might do a video over it using a phone :/) and you clip in the wall using epona. From there you climb up and I just spammed the jump button to clump up and popped up there on top (not literally "pop up")