Somewhat of a copypasta from an earlier comment of mine, but I'd just be recommending the same games anyway:

The Witness - a masterpiece of puzzle and level design, definitely expanded my mind. Nothing in that game is frivolous. Might be a little confusing at first, but if you explore and experiment its rules will become clearer to you.

The Outer Wilds - a technical masterpiece and a game where you can beat the game very quickly if you know what to do, but you have to put in about 10-15 hours of exploration all across a solar system to gain the knowledge of what you need to do in order to beat it. An excellent creepy, puzzly, and deadly mystery. Also a little different than other games in that instead of collecting trinkets and doo dads, what you're collecting is pieces of knowledge at different locations that can help you figure out mysteries at other places, and see some incredible landscapes that interact with each other and change over time.

Persona 5 Royal - The combat can get a little samey in this game, but the style, soundtrack, and world is amazing. Also love how you have to decide what activities you spend your free time on, as you can only do a few at a time.

Danganronpa series - Bonkers murder mystery graphic novel that's very creative story stretches across multiple games. Figuring out who killed who can take some lateral thinking. It uses pink blood so it doesn't seem super gory but the deaths are kind of dark if you think about it too much. It's a pretty mature game. Phoenix Wright games can give a similar experience but are much more wholesome and more appropriate for younger audiences. Still about solving murders though.

Civilization series - masterpiece of 'just one more turn' gameplay. I don't play it too many times in a year, but whenever I do sit down to play it again, I tend to lose a weekend to it. And it might lead them to go "hey that Terracotta Army is pretty cool, let's look that up on Wikipedia and find out more about it"

Baba Is You - clever puzzle that requires you to change your thinking entirely to solve its puzzles, as by pushing together and breaking apart words of sentences (as if they're blocks) you can change the rules of the level in very surprising ways. You really need to think outside of the box to solve these puzzles.

Zelda: Breath of the Wild - a huge world to explore that just barf a bunch of icons on the map and tells you to go there to do some minigame thing like Ubisoft does. You see something that looks different and interesting in the distance? Go there, and you will likely be rewarded. Also tons of interesting physics puzzles that require some brain scratching to figure out.

God of War - great story, feels like you're playing a movie at times, gorgeous visuals, super fluid combat (actually tried going back to breath of the wild after a playthrough of this and BOTW's combat felt pretty boring in comparison), and even some clever puzzles thanks to being able to throw an axe that freezes things that you can recall from anywhere.

Into The Breach - Clever tactics game, kind of like chess in an environment with mechs, that helped refresh the formula by telling you exactly what the enemy is about to do on their next turn, so it becomes a puzzle in figuring out how to minimize or redirect their targets/movements and/or who needs to be eliminated most this turn.