Kona stinky 24, Norco B line, Commencal supreme 24, Spesh Big hit grom or YT industries First Play.
The YT is probably the best off the shelf but, would be difficult to find. Then the Commencal but, pretty expensive. All the others need better (air) suspension to be any good.
There is also the lil shredder phenom but, that’s mega bucks.
If the kid is tall, a small adult bike with 24in wheels might be worth considering as it would give more room for growth before having to change again.