The problem with Metalworker is the same as all three-mana creatures, and it was enough to sink all the others
PSA Population Reports PSA grades both Japanese and English cards, and the pop reports tell an interesting story: Japanese cards have higher PSA 10 rates
Elsa, Spirit of Winter can herself quest for a mighty three lore and challenge with four strength, making the Amethyst card pretty powerful across the board
You already play it with other creatures, and +2/+2 is incredible if you have even a couple of other creatures to swing with
Since nearly every Pokmon deck runs basic Energy cards, theres a decently high floor for the demand from collector-players for high-rarity Energy cards that match the other high-rarity cards in Standard, even when all the other cards in a set are lackluster
However, we're not listing cards' values in their etched foil price as that market is still very fluid, and thus not all cards' foil etched versions have prices yet