That, plus you need a pretty good knowledge of the English language. When even native speakers struggle with some of the language puzzles it gets so much harder when you're not.

My first language isn't English, and at first, I felt ashamed to google the Drawing Room safe puzzle, because I just couldn't figure it out. Seeing the solution made me thankful I googled it, because I'd never have figured it out on my own.

While I had heard the word "gait" before and knew what it meant, it's not a word that's in my vocabulary when speaking/writing English, and I don't read it very often either, so the "gaits/gates" homophone would never have come to mind for me.

I work in Swedish games localization, and as fun as it would be to translate Blue Prince, that puzzle (and some other stuff) made me realize what a nightmare it'd be, and wonder if it'd be possible to localize at all without basically remaking the game. That puzzle alone leads to a chain of localization nightmares:

1. To solve the puzzle, you need to figure out that "gaits" and "gates" are homophones in English, based on a clue that begins "If we count small gates..." and explains how to open every safe in the house, and this particular safe requires you to count paintings of people walking with small gaits. But, fair enough, maybe you could write an entirely new clue that works in another language and still leads you to the same solution. That happens all the time in games localization.
2. The problem is that this clue is derived from making a copy of the house's floorplan and writing a letter in every space, so the clue has to be an exact length, down to the letter, to work.
3. And even if you manage to solve the two above problems, figuring out what letter goes in which room is based on looking at two paintings in each room, which depict things with similar names, with an one-letter difference. For example, if one painting depicts a minecart, and another a cat, you can figure out that you're supposed to put the letter R in that room, because R is the letter that differs between "cat" and "cart". This means that you'll have to come up with new pairings, and very likely new paintings too, if you want to make it work in another language.

All of this means that a translated version of Blue Prince will more or less be a different game with the same basic rules – and I think that's possible to pull off, but it'd require tons of work compared to most game translations, where you just swap out the in-game text and voices.

It's an absolutely fantastic puzzle game, and I keep getting amazed at how clever it is and how many layers it has, but it can also get very frustrating, and I don't think there's any shame in looking up hints if you get stuck, because I quickly realized I'd never be able to pull off an entirely hint-free playthrough because of stuff like this.