For the Harder Struggling Statue, you can set the game to easy mode and manipulate the jsons to make the ghosts on that floor deal zero damage. Yeah, I know, not legit, but the game is about trading health, so I can't be bothered.
For Horde Mode, you should start a run on hard mode and herd the ghosts like the guide said, so it shouldn't be that hard.
For Glass Cannon, again, either set a ghost's Json to take away 1 point of maximum health, preferably one you can easily avoid, then clear the floor, or find Sand snare, if you are on that sort of floor. And if you have a curse you don't like, accept to have your curse lifted in exchange for your vitality. You are going to be stuck at 50 health for P.Y.W, so you may as well start getting used to it.
I think you might also be able to just leave the mansion at the beginning of the game instead of entering to get the coward/nope, copy it, and rename it to all of these achievement names. I didn't test to see if it unlocks the challenge or not, but you can just do a fresh install if it doesn't;
These images right here are the files you need, which goes in C:\Users\YOURNAMEHERE\AppData\Local\Ghosts_and_Japes\resources. Now, all you have to do is get an achievement, copy the file, rename it to the achievement you want. Now I don't know which ones correspond to the achievement you want, but I'd wager it's the ach_msc_riskyunhealthy, ach_msc_quickkiller, and ach_msc_nohit files. Also, reminder, make you try to get the drill and enough money BEFORE you enter the Dark Halls Seed doesn't give you a drill when you DO get to the Dark Halls, again, just pause, copy the save file, put it somewhere else, just in case the game screws you over, especially with regards to the secret room. No, I'm not giving you the file name for Proving Your Worth.