More than anything, these moments seem to be self-perpetuating, where everyone gets tremendously excited about one particular card, which creates demand, which raises the price, which exaggerates the rarity, which creates demand The next most expensive right now is the Latias ex at almost $200, then the gold card version of the Pikachu ex at $100, and that Hydreigon pictured above at about $95
Such card type was called reverse because a regular Holofoil will have a shiny metallic finish all around the card, including the artwork
"GBA Platformer of the Year One Piece"
But just copying your foe's thing means you cannot Clone what your deck was built around - your stuff
Similarly, if The Soul Stone is already harnessed and becomes a copy of something else, it stays harnessed, though it's very likely that won't be relevant until that copy effect ends