Assuming no "break the timeline/change history" shenanigans, if you could visit your child self and show them one video game from the present, what would it be, and why?

Any PS5 game would have destroyed every cell in my brain on contact. It would have been like skydiving into a black hole. Just POOF... nothing but atoms.

I'm not sure if this is the answer, but I was just playing Assassin's Creed: Shadows, so that one. There's several reasons for that:

• I was quite interesting in playing Tenchu (mainly the second one) as a child. I never got around to it, but I'm sure I would have enjoyed a game with a similar setting and probably better gameplay too. I'm still hoping to play Tenchu some day, so perhaps Tenchu gameplay is better, but it's not a high priority anymore, so we'll see.
• Open world games would've been amazing when I was a child, let alone one with such a huge world.
• It's a gorgeous game in many ways, so obviously that's something to show off.

Very good question.

It'll probably be a VR game like Resi 7 or Intruders Hide & Seek VR. I loved horror as a kid. I started Playing the Resi PS1 games when I was 8 or 9.
Or maybe Mario Odyssey. I've always loved Mario games since I was about 4.
Or maybe Minecraft because I know I would have loved that as a kid :)

This is a hard but intriguing question. It's hard to choose between and I bet more answers will come to me over time.

Age of Empires II: Definitive Edition

My child self was fond of the original game, and would probably have their mind blown by the game being supported well into the 2020's. However, it would also be a good object lesson on how the nature of video games has changed, since compared to yesteryear, developers will endlessly iterate on older games rather than making something entirely new very often. And to prove my point, I'll explain that Age of Empires IV is the most recent game in the series.

Asassins crees oddesey and say to my childself look how great this game looks!
Look how massive the world is just like how we pictured it
But their is nothing to do in it.

Hm...something VR definitely...not sure what though. As sci-fi nerd, probably Elite Dangerous VR (as someone who grew up with Elite) or No Man's Sky VR. Or non-VR, but to keep it in space, Kerbal Space Program for it's build/fly rockets/spacehips with realistic physics.