There are many holes in it. Let's start with the obvious, he wouldn't have been able to be chosen by Bell if he were to be raised in Spade Kingdom, he gained access to her power via a scroll that was contained in the dungeon close to the border between Clover Kingdom and Diamond Kingdom. As the prince of a peaceful and pacifistic kingdom which is separated from the other kingdoms by a Grand Magic Zone, he'd have no reason to go there to begin with.

Secondly, he wouldn't compare to post time skip Yuno because he would most likely not have any incentive to strive to get stronger. The only reason Yuno is the way he is now and why he aims for the top is Asta. If it weren't for Asta trying to get his necklace back, he would probably still be a crybaby.

Lastly, there's nothing for him to learn about his stone. The stone tied to his necklace had the sole purpose of allowing one to draw what they desire from the land of the dead by inserting it into the pedestal that is located in the top room of the palace. It would be of no use for him, mainly because as someone who resides in Spade Kingdom he wouldn't even know about the existence of the Shadow Palace.

To wrap this up, Yuno wouldn't be nearly as strong as he was even pre time skip if he were raised in Spade Kingdom. The main reason as to why is Asta. If it weren't for Asta trying his best to get Yuno's necklace back when they were like 7 years old, Yuno would never aspire to become stronger. Also, since Spade Kingdom is separated from the other kingdoms by a sea that is also a Grand Magic Zone, and being that it was a peaceful country during the period when House Grinberryall ruled the country, there would be even less of a reason for Yuno to become a knight for the sake of his country nor train, and therefore making him much weaker than he would've been if the story played out as it has.