I might be out of date but for a long time my 2 nephews (10 and 13, cousins to each other) have been playing Blox Fruits, which I understand is pretty much a standard "grind" MMORPG. (Which I don't necessarily find that bad; having to put a lot of work in a character and seeing it grow slowly and steadily can be a lesson.) I like how they are having fun trying to coordinate and take out a boss together (sometimes dying all the time), but I suppose other games can give that, perhaps even better-looking ones and certainly ones made by less shady companies. (Oh, and actually working on Linux/steam deck)

So I was wondering if there are other games that I could introduce them to, if only to remind them that world outside Roblox exists. I never played any MMORPG's (or pretty much anything multi-player, except Minecraft/Terraria/etc. with the kids) so I'm out of the picture. I've only tried few in my life and never stuck for long.

Albion Online seemed child-like enough, albeit a little boring for my taste. One I really enjoyed recently is Path of Exile (and I it looks more than good enough to be hard to resist for a kid), but who knows -- is that safe for 10 to 13 year olds...?