^^^ Same ICSW, all the easy ones follow some sort of simple pattern, or were just mainly events (cheren)
here were, not the hardest, but the most cringe gym puzzles out there:
Kanto: Sabrina - Fucking teleport puzzles. ugh.
Johto: Chuck - I had to walk around the gym and it was very tedious
Hoenn: Wallace/Juan - I really, really hate those puzzles where when you make one mistake you have to restart it.
Sinnoh: Byron - the puzzle itself was really easy, but i was really young at the time, so i thought that all the decorative jet fuel cant melt steel beams were part of the puzzle and i got really confused.
Unova/Kalos: Ez Pz 100% of the way. Gamefreak, please make challenging puzzles for us tyvm.