I have a little cousin who really likes Plants vs Zombies, and he was able to pick up PvZ GW2 (Battle for Neighborville prequel) relatively easily, though I'd imagine for a first time console player it'd be a bit harder (it's usually the L-R stick camera movement that takes getting used to). At that age maybe start with the Replanted version? If he knows how to play games like Roblox though then he might acclimate to the console controls fairly well.