ORAS was as "challenging" as you would expect a Pokémon game to be from my experience, there are things I could have done to make my Pokémon over-leveled by keeping the EXP share on, exploring everywhere in the game as soon as I could (I didn't go through the water routes where Sea Mauville is, didn't go to Laverige (Spelling?) Town, didn't explore the "desert" until just before the Elite 4 because I decided just before doing the elite 4 I wanted to use a dark type and went to catch an Absol and it needed level upping before I did the Elite 4 (although training the Sharpedo I was using as my Surf/Diver could have been possible too, I just didn't want to), could have using the (mega) Latios (played OR) we are given for free (I liked how we can control the nature / IVs(to an extent) using the method in ORAS instead of it roaming). Also I played the game on set not switch.
Nothing in the game was difficult however, mega Swampert was too good from my experience (beat Wallace/Drake/Steven on its own, regular Swampert wouldn't have been able to do so, which made half wish we didn't get mega bracelet until post game or something because it was just a win button to mega evolve, it was level 58 vs. Steven), opponents pokemon not being Ev trained gives a huge advantage later in the game(even if disrupted evenly or only significant trainers having Ev'd pokemon would have made things more even). The most difficult parts were the large amounts of pokemon using confuse ray in the game, that was what caused most of the pokemon that did faint to faint.
GF gave the option to making the game too easy, I can imagine struggling as an 9 year old with the knowledge I had of Pokemon back then playing this, especially first playing through, although GF did help with a couple of little things such as when the TEAM was in Slatport all you had to do was enter the building to find the guy to let you get into the museum, I remember struggling with that during one of my playthroughs of Sapphire as a kid, also they let you teleport to Petelburg after 4th gym something I remember taking out the booklet that came with the game to try figure out how to progress through the game. Which I actually think is a good thing, imagine playing the game with terrible nature and not knowing the difference between physical and special moves, or even the typing of the pokemon you are playing against, that would make the game a bit challenging in my opinion.
This is all only looking through it from battling I haven't had time to start trying contests and all. I have gotten stuck at the 3rd (The one with Strength) trick house which I don't want to look up how to do because I haven't looked up anything about how to in this game other than mega stone locations and how to get 2 bikes, and the Shoal Cave time of day thing (which I was using for trying to get Slowbroite).